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Section 1: 10-Q (MDU RESOURCES FORM 10-Q 09-30-2018)

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UNITED STATES SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 10-Q
ý QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the quarterly period ended September 30, 2018
OR
o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from _____________ to ______________
Commission file number 1-03480
MDU RESOURCES GROUP, INC.
(Exact name of registrant as specified in its charter)
Delaware
 
41-0423660
(State or other jurisdiction of
incorporation or organization)
 
(I.R.S. Employer Identification No.)

1200 West Century Avenue
P.O. Box 5650
Bismarck, North Dakota 58506-5650
(Address of principal executive offices)
(Zip Code)
(701) 530-1000
(Registrant's telephone number, including area code)

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ý No o.
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ý No o.
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.
Large accelerated filer ý
Accelerated filer o
Non-accelerated filer o
Smaller reporting company o
 
Emerging growth company o
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o No ý.
Indicate the number of shares outstanding of each of the issuer's classes of common stock, as of October 26, 2018: 196,018,324 shares.





Index
 
Page
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Item 1
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Item 2
 
 
 
Item 3
 
 
 
Item 4
 
 
 
 
 
 
 
Item 1
 
 
 
Item 1A
 
 
 
Item 2
 
 
 
Item 4
 
 
 
Item 6
 
 
 
 
 
 

2



Definitions
The following abbreviations and acronyms used in this Form 10-Q are defined below:
Abbreviation or Acronym
 
2017 Annual Report
Company's Annual Report on Form 10-K for the year ended December 31, 2017
AFUDC
Allowance for funds used during construction
ASC
FASB Accounting Standards Codification
ASU
FASB Accounting Standards Update
Brazilian Transmission Lines
Company's former investment in companies owning three electric transmission lines in Brazil
BSSE
345-kilovolt transmission line from Ellendale, North Dakota, to Big Stone City, South Dakota
Calumet
Calumet Specialty Products Partners, L.P.
Cascade
Cascade Natural Gas Corporation, an indirect wholly owned subsidiary of MDU Energy Capital
Centennial
Centennial Energy Holdings, Inc., a direct wholly owned subsidiary of the Company
Centennial Capital
Centennial Holdings Capital LLC, a direct wholly owned subsidiary of Centennial
Centennial Resources
Centennial Energy Resources LLC, a direct wholly owned subsidiary of Centennial
Company
MDU Resources Group, Inc.
Coyote Creek
Coyote Creek Mining Company, LLC, a subsidiary of The North American Coal Corporation
Coyote Station
427-MW coal-fired electric generating facility near Beulah, North Dakota (25 percent ownership)
Dakota Prairie Refinery
20,000-barrel-per-day diesel topping plant built by Dakota Prairie Refining in southwestern North Dakota
Dakota Prairie Refining
Dakota Prairie Refining, LLC, a limited liability company previously owned by WBI Energy and Calumet (previously included in the Company's refining segment)
dk
Decatherm
Dodd-Frank Act
Dodd-Frank Wall Street Reform and Consumer Protection Act
EPA
United States Environmental Protection Agency
Exchange Act
Securities Exchange Act of 1934, as amended
FASB
Financial Accounting Standards Board
FERC
Federal Energy Regulatory Commission
Fidelity
Fidelity Exploration & Production Company, a direct wholly owned subsidiary of WBI Holdings (previously referred to as the Company's exploration and production segment)
GAAP
Accounting principles generally accepted in the United States of America
GHG
Greenhouse gas
Great Plains
Great Plains Natural Gas Co., a public utility division of the Company
Intermountain
Intermountain Gas Company, an indirect wholly owned subsidiary of MDU Energy Capital
Knife River
Knife River Corporation, a direct wholly owned subsidiary of Centennial
Knife River - Northwest
Knife River Corporation - Northwest, an indirect wholly owned subsidiary of Knife River
kWh
Kilowatt-hour
LWG
Lower Willamette Group
MD&A
Management's Discussion and Analysis of Financial Condition and Results of Operations
MDU Construction Services
MDU Construction Services Group, Inc., a direct wholly owned subsidiary of Centennial
MDU Energy Capital
MDU Energy Capital, LLC, a direct wholly owned subsidiary of the Company
MISO
Midcontinent Independent System Operator, Inc.
MMcf
Million cubic feet
MMdk
Million dk
MNPUC
Minnesota Public Utilities Commission
Montana-Dakota
Montana-Dakota Utilities Co., a public utility division of the Company
MTPSC
Montana Public Service Commission
MW
Megawatt
NDPSC
North Dakota Public Service Commission
Non-GAAP
Not in accordance with GAAP

3



OPUC
Oregon Public Utility Commission
Oregon DEQ
Oregon State Department of Environmental Quality
Pronghorn
Natural gas processing plant located near Belfield, North Dakota (WBI Energy Midstream's 50 percent ownership interests were sold effective January 1, 2017)
PRP
Potentially Responsible Party
ROD
Record of Decision
SDPUC
South Dakota Public Utilities Commission
SEC
United States Securities and Exchange Commission
SSIP
System Safety and Integrity Program
TCJA
Tax Cuts and Jobs Act
Tesoro
Tesoro Refining & Marketing Company LLC
VIE
Variable interest entity
Washington DOE
Washington State Department of Ecology
WBI Energy
WBI Energy, Inc., a direct wholly owned subsidiary of WBI Holdings
WBI Energy Midstream
WBI Energy Midstream, LLC, an indirect wholly owned subsidiary of WBI Holdings
WBI Energy Transmission
WBI Energy Transmission, Inc., an indirect wholly owned subsidiary of WBI Holdings
WBI Holdings
WBI Holdings, Inc., a direct wholly owned subsidiary of Centennial
WUTC
Washington Utilities and Transportation Commission
WYPSC
Wyoming Public Service Commission

4



Forward-Looking Statements
This Form 10-Q contains forward-looking statements within the meaning of Section 21E of the Exchange Act. Forward-looking statements are all statements other than statements of historical fact, including without limitation those statements that are identified by the words "anticipates," "estimates," "expects," "intends," "plans," "predicts" and similar expressions, and include statements concerning plans, objectives, goals, strategies, future events or performance, and underlying assumptions (many of which are based, in turn, upon further assumptions) and other statements that are not statements of historical facts. From time to time, the Company may publish or otherwise make available forward-looking statements of this nature, including statements contained within Part I, Item 2 - MD&A - Business Segment Financial and Operating Data.
Forward-looking statements involve risks and uncertainties, which could cause actual results or outcomes to differ materially from those expressed. The Company's expectations, beliefs and projections are expressed in good faith and are believed by the Company to have a reasonable basis, including without limitation, management's examination of historical operating trends, data contained in the Company's records and other data available from third parties. Nonetheless, the Company's expectations, beliefs or projections may not be achieved or accomplished.
Any forward-looking statement contained in this document speaks only as of the date on which the statement is made, and the Company undertakes no obligation to update any forward-looking statement or statements to reflect events or circumstances that occur after the date on which the statement is made or to reflect the occurrence of unanticipated events. New factors emerge from time to time, and it is not possible for management to predict all of the factors, nor can it assess the effect of each factor on the Company's business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statement. All forward-looking statements, whether written or oral and whether made by or on behalf of the Company, are expressly qualified by the risk factors and cautionary statements reported in Part II, Item 1A - Risk Factors in this Form 10-Q, Part I, Item 1A - Risk Factors in the 2017 Annual Report and subsequent filings with the SEC.
Introduction
The Company is a regulated energy delivery and construction materials and services business, which was incorporated under the laws of the state of Delaware in 1924. Its principal executive offices are at 1200 West Century Avenue, P.O. Box 5650, Bismarck, North Dakota 58506-5650, telephone (701) 530-1000.
Montana-Dakota, Great Plains, Cascade and Intermountain comprise the natural gas distribution segment. Montana-Dakota also comprises the electric segment.
The Company, through its wholly owned subsidiary, Centennial, owns WBI Holdings, Knife River, MDU Construction Services, Centennial Resources and Centennial Capital. WBI Holdings is the pipeline and midstream segment, Knife River is the construction materials and contracting segment, MDU Construction Services is the construction services segment, and Centennial Resources and Centennial Capital are both reflected in the Other category.
For more information on the Company's business segments, see Note 14.

5



Part I -- Financial Information
Item 1. Financial Statements
MDU Resources Group, Inc.
Consolidated Statements of Income
(Unaudited)
 
 
Three Months Ended
 
Nine Months Ended
 
 
September 30,
 
September 30,
 
 
2018

2017

 
2018

2017

 
 
(In thousands, except per share amounts)
Operating revenues:
 
 
 
 
 
 
Electric, natural gas distribution and regulated pipeline and midstream
 
$
200,617

$
206,936

 
$
851,761

$
866,035

Nonregulated pipeline and midstream, construction materials and contracting, construction services and other
 
1,080,170

1,065,612

 
2,469,917

2,412,077

Total operating revenues 
 
1,280,787

1,272,548

 
3,321,678

3,278,112

Operating expenses:
 
 

 

 
 

 

Operation and maintenance:
 
 

 

 
 

 

Electric, natural gas distribution and regulated pipeline and midstream
 
82,920

80,204

 
252,961

237,881

Nonregulated pipeline and midstream, construction materials and contracting, construction services and other
 
913,671

893,762

 
2,166,570

2,116,575

Total operation and maintenance
 
996,591

973,966

 
2,419,531

2,354,456

Purchased natural gas sold
 
32,123

33,319

 
270,319

283,936

Depreciation, depletion and amortization
 
55,016

52,155

 
161,298

155,138

Taxes, other than income
 
38,647

38,882

 
128,257

127,273

Electric fuel and purchased power
 
18,406

18,906

 
58,901

57,544

Total operating expenses
 
1,140,783

1,117,228

 
3,038,306

2,978,347

Operating income
 
140,004

155,320

 
283,372

299,765

Other income
 
2,683

2,068

 
4,864

6,212

Interest expense
 
20,955

20,909

 
62,202

61,978

Income before income taxes
 
121,732

136,479

 
226,034

243,999

Income taxes
 
14,363

46,930

 
32,629

74,406

Income from continuing operations
 
107,369

89,549

 
193,405

169,593

Income (loss) from discontinued operations, net of tax (Note 10)
 
(118
)
(2,198
)
 
85

(3,702
)
Net income
 
107,251

87,351

 
193,490

165,891

Loss on redemption of preferred stocks
 


 

600

Dividends declared on preferred stocks
 


 

171

Earnings on common stock
 
$
107,251

$
87,351

 
$
193,490

$
165,120

Earnings per common share - basic:
 
 

 

 
 

 

Earnings before discontinued operations
 
$
.55

$
.46

 
$
.99

$
.86

Discontinued operations, net of tax
 

(.01
)
 

(.01
)
Earnings per common share - basic
 
$
.55

$
.45

 
$
.99

$
.85

Earnings per common share - diluted:
 
 

 

 
 

 

Earnings before discontinued operations
 
$
.55

$
.46

 
$
.99

$
.86

Discontinued operations, net of tax
 

(.01
)
 

(.02
)
Earnings per common share - diluted
 
$
.55

$
.45

 
$
.99

$
.84

Dividends declared per common share
 
$
.1975

$
.1925

 
$
.5925

$
.5775

Weighted average common shares outstanding - basic
 
196,018

195,304

 
195,618

195,304

Weighted average common shares outstanding - diluted
 
196,265

195,783

 
196,104

195,922

The accompanying notes are an integral part of these consolidated financial statements.

6



MDU Resources Group, Inc.
Consolidated Statements of Comprehensive Income
(Unaudited)
 
 
Three Months Ended
Nine Months Ended
 
 
September 30,
September 30,
 
 
2018

2017

2018
2017
 
 
(In thousands)
Net income
 
$
107,251

$
87,351

$
193,490

$
165,891

Other comprehensive income:
 
 
 
 
 
Reclassification adjustment for loss on derivative instruments included in net income, net of tax of $55 and $56 for the three months ended and $164 and $168 for the nine months ended in 2018 and 2017, respectively
 
92

92

279

275

Postretirement liability adjustment:
 
 
 
 
 
Amortization of postretirement liability losses included in net periodic benefit cost (credit), net of tax of $142 and $203 for the three months ended and $442 and $609 for the nine months ended in 2018 and 2017, respectively
 
442

333

1,309

1,002

Reclassification of postretirement liability adjustment from regulatory asset, net of tax of $0 and $0 for the three months ended and $0 and $(725) for the nine months ended in 2018 and 2017, respectively
 



(917
)
Postretirement liability adjustment
 
442

333

1,309

85

Foreign currency translation adjustment:
 
 
 
 
 
Foreign currency translation adjustment recognized during the period, net of tax of $0 and $9 for the three months ended and $(14) and $5 for the nine months ended in 2018 and 2017, respectively
 

15

(61
)
9

Reclassification adjustment for foreign currency translation adjustment included in net income, net of tax of $0 and $0 for the three months ended and $75 and $0 for the nine months ended in 2018 and 2017, respectively
 


249


Foreign currency translation adjustment
 

15

188

9

Net unrealized gain (loss) on available-for-sale investments:
 
 
 
 
 
Net unrealized loss on available-for-sale investments arising during the period, net of tax of $(13) and $(10) for the three months ended and $(52) and $(38) for the nine months ended in 2018 and 2017, respectively
 
(51
)
(19
)
(199
)
(70
)
Reclassification adjustment for loss on available-for-sale investments included in net income, net of tax of $9 and $14 for the three months ended and $26 and $50 for the nine months ended in 2018 and 2017, respectively
 
33

27

97

93

Net unrealized gain (loss) on available-for-sale investments
 
(18
)
8

(102
)
23

Other comprehensive income
 
516

448

1,674

392

Comprehensive income attributable to common stockholders
 
$
107,767

$
87,799

$
195,164

$
166,283

The accompanying notes are an integral part of these consolidated financial statements.



7



MDU Resources Group, Inc.
Consolidated Balance Sheets
(Unaudited)
 
September 30, 2018

September 30, 2017

December 31, 2017

(In thousands, except shares and per share amounts)
 
Assets
 
 
 
Current assets:
 
 
 
Cash and cash equivalents
$
67,077

$
37,356

$
34,599

Receivables, net
787,344

739,402

727,030

Inventories
270,293

232,555

226,583

Prepayments and other current assets
88,760

89,625

81,304

Current assets held for sale
571

304

479

Total current assets
1,214,045

1,099,242

1,069,995

Investments
143,303

133,895

137,613

Property, plant and equipment
7,102,960

6,658,891

6,770,829

Less accumulated depreciation, depletion and amortization
2,796,649

2,667,762

2,691,641

Net property, plant and equipment
4,306,311

3,991,129

4,079,188

Deferred charges and other assets:
 

 

 

Goodwill
640,203

631,791

631,791

Other intangible assets, net
4,318

4,209

3,837

Other
408,178

419,846

407,850

Noncurrent assets held for sale
1,835

64,333

4,392

Total deferred charges and other assets 
1,054,534

1,120,179

1,047,870

Total assets
$
6,718,193

$
6,344,445

$
6,334,666

Liabilities and Stockholders' Equity
 

 

 

Current liabilities:
 

 

 

Long-term debt due within one year
$
3,915

$
148,499

$
148,499

Accounts payable
339,713

304,101

312,327

Taxes payable
50,461

108,946

42,537

Dividends payable
38,714

37,596

38,573

Accrued compensation
62,836

67,097

72,919

Other accrued liabilities
221,620

184,580

186,010

Current liabilities held for sale
7,959

5,749

11,993

Total current liabilities 
725,218

856,568

812,858

Long-term debt
1,911,555

1,592,053

1,566,354

Deferred credits and other liabilities:
 

 

 

Deferred income taxes
405,761

652,413

347,271

Other
1,154,366

889,494

1,179,140

Total deferred credits and other liabilities 
1,560,127

1,541,907

1,526,411

Commitments and contingencies






Stockholders' equity:
 

 

 

Common stock
 

 

 

Authorized - 500,000,000 shares, $1.00 par value
Shares issued - 196,557,245 at September 30, 2018 and 195,843,297 at
September 30, 2017 and December 31, 2017
196,557

195,843

195,843

Other paid-in capital
1,247,151

1,232,766

1,233,412

Retained earnings
1,124,830

964,275

1,040,748

Accumulated other comprehensive loss
(43,619
)
(35,341
)
(37,334
)
Treasury stock at cost - 538,921 shares
(3,626
)
(3,626
)
(3,626
)
Total stockholders' equity
2,521,293

2,353,917

2,429,043

Total liabilities and stockholders' equity 
$
6,718,193

$
6,344,445

$
6,334,666

The accompanying notes are an integral part of these consolidated financial statements.

8



MDU Resources Group, Inc.
Consolidated Statements of Equity
(Unaudited)
Nine Months Ended September 30, 2018
 
 
 
 
 
 
 
 
 
Other
Paid-in Capital

Retained Earnings

Accumu-lated
Other Compre-hensive Loss

 
 
 
 
Common Stock
Treasury Stock
 
 
Shares

Amount

Shares

Amount

Total

 
(In thousands, except shares)
Balance at December 31, 2017
195,843,297

$
195,843

$
1,233,412

$
1,040,748

$
(37,334
)
(538,921
)
$
(3,626
)
$
2,429,043

Cumulative effect of adoption of ASU 2014-09



(970
)



(970
)
Adjusted balance at January 1, 2018
195,843,297

195,843

1,233,412

1,039,778

(37,334
)
(538,921
)
(3,626
)
2,428,073

Net income



193,490




193,490

Other comprehensive income




1,674



1,674

Reclassification of certain prior period tax effects from accumulated other comprehensive loss



7,959

(7,959
)



Dividends declared on common stock



(115,998
)



(115,998
)
Stock-based compensation


3,810

(399
)



3,411

Repurchase of common stock





(182,424
)
(5,020
)
(5,020
)
Issuance of common stock upon vesting of stock-based compensation, net of shares used for tax withholdings


(7,350
)


182,424

5,020

(2,330
)
Issuance of common stock
713,948

714

17,279





17,993

Balance at September 30, 2018
196,557,245

$
196,557

$
1,247,151

$
1,124,830

$
(43,619
)
(538,921
)
$
(3,626
)
$
2,521,293


Nine Months Ended September 30, 2017
 
 
 
 
 
 
 
 
 
 
Other
Paid-in Capital

Retained Earnings

Accumu-lated
Other Compre-hensive Loss

 
 
 
 
Preferred Stock
Common Stock
Treasury Stock
 
 
Shares

Amount

Shares

Amount

Shares

Amount

Total

 
(In thousands, except shares)
Balance at December 31, 2016
150,000

$
15,000

195,843,297

$
195,843

$
1,232,478

$
912,282

$
(35,733
)
(538,921
)
$
(3,626
)
$
2,316,244

Net income





165,891




165,891

Other comprehensive income






392



392

Dividends declared on preferred stocks





(171
)



(171
)
Dividends declared on common stock





(112,788
)



(112,788
)
Stock-based compensation




2,729

(339
)



2,390

Repurchase of common stock







(64,384
)
(1,684
)
(1,684
)
Issuance of common stock upon vesting of stock-based compensation, net of shares used
for tax withholdings




(2,441
)


64,384

1,684

(757
)
Redemption of preferred stock
(150,000
)
(15,000
)



(600
)



(15,600
)
Balance at September 30, 2017

$

195,843,297

$
195,843

$
1,232,766

$
964,275

$
(35,341
)
(538,921
)
$
(3,626
)
$
2,353,917



9



MDU Resources Group, Inc.
Consolidated Statements of Cash Flows
(Unaudited)
 
 
Nine Months Ended
 
 
September 30,
 
 
2018

2017

 
 
(In thousands)
Operating activities:
 
 
 
Net income
 
$
193,490

$
165,891

Income (loss) from discontinued operations, net of tax
 
85

(3,702
)
Income from continuing operations
 
193,405

169,593

Adjustments to reconcile net income to net cash provided by operating activities:
 
 

 

Depreciation, depletion and amortization
 
161,298

155,138

Deferred income taxes
 
42,428

(16,777
)
Changes in current assets and liabilities, net of acquisitions:
 
 

 
Receivables
 
(55,749
)
(121,128
)
Inventories
 
(38,785
)
2,047

Other current assets
 
(3,452
)
(40,655
)
Accounts payable
 
16,155

30,097

Other current liabilities
 
31,971

66,647

Other noncurrent changes
 
(27,170
)
(15,081
)
Net cash provided by continuing operations
 
320,101

229,881

Net cash provided by (used in) discontinued operations
 
(2,720
)
42,020

Net cash provided by operating activities
 
317,381

271,901

Investing activities:
 
 

 

Capital expenditures
 
(345,599
)
(222,084
)
Acquisitions, net of cash acquired
 
(27,858
)

Net proceeds from sale or disposition of property and other
 
12,451

121,162

Investments
 
(1,560
)
(260
)
Net cash used in continuing operations
 
(362,566
)
(101,182
)
Net cash provided by discontinued operations
 
1,236

2,234

Net cash used in investing activities
 
(361,330
)
(98,948
)
Financing activities:
 
 

 

Issuance of long-term debt
 
356,952

133,437

Repayment of long-term debt
 
(157,315
)
(183,968
)
Dividends paid
 
(115,859
)
(113,131
)
Redemption of preferred stock
 

(15,600
)
Repurchase of common stock
 
(5,020
)
(1,684
)
Tax withholding on stock-based compensation
 
(2,330
)
(757
)
Net cash provided by (used in) continuing operations
 
76,428

(181,703
)
Net cash provided by discontinued operations
 


Net cash provided by (used in) financing activities
 
76,428

(181,703
)
Effect of exchange rate changes on cash and cash equivalents
 
(1
)
(1
)
Increase (decrease) in cash and cash equivalents
 
32,478

(8,751
)
Cash and cash equivalents -- beginning of year
 
34,599

46,107

Cash and cash equivalents -- end of period
 
$
67,077

$
37,356

The accompanying notes are an integral part of these consolidated financial statements.

10



MDU Resources Group, Inc.
Notes to Consolidated
Financial Statements
September 30, 2018 and 2017
(Unaudited)
Note 1 - Basis of presentation
The accompanying consolidated interim financial statements were prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Interim financial statements do not include all disclosures provided in annual financial statements and, accordingly, these financial statements should be read in conjunction with those appearing in the 2017 Annual Report. The information is unaudited but includes all adjustments that are, in the opinion of management, necessary for a fair presentation of the accompanying consolidated interim financial statements and are of a normal recurring nature. Depreciation, depletion and amortization expense is reported separately on the Consolidated Statements of Income and therefore is excluded from the other line items within operating expenses. Management has also evaluated the impact of events occurring after September 30, 2018, up to the date of issuance of these consolidated interim financial statements.
On December 22, 2017, President Trump signed into law the TCJA which includes lower corporate tax rates, repealing the domestic production deduction, disallowance of immediate expensing for regulated utility property and modifying or repealing many other business deductions and credits. The reduction in the corporate tax rate was effective on January 1, 2018, reducing the Company's income tax expense for 2018. The Company continues to review the components of the TCJA and the impact on the Company's consolidated financial statements and related disclosures for 2018 and thereafter.
While the Company was able to make reasonable estimates of the impact of the reduction in corporate tax rate on the Company's net deferred tax liabilities during the fourth quarter of 2017, such estimates may be affected by other analyses related to the TCJA, including, but not limited to, the state tax effect of adjustments to federal temporary differences and the calculation of deemed repatriation of deferred foreign income. The final transition impacts of the TCJA may differ from amounts disclosed, possibly materially, due to, among other things, interpretations, legislative action to address questions, changes in accounting standards for income taxes or related interpretations, or updates or changes to estimates the Company has utilized to calculate the transition impacts. The SEC has issued rules that would allow for a measurement period of up to one year after the enactment date of the TCJA to finalize the recording of the related tax impacts, of which there were no such material adjustments during the nine months ended September 30, 2018. The Company currently anticipates finalizing and recording any resulting adjustments by December 31, 2018, which will be included in income from continuing operations.
Due to the enactment of the TCJA, the regulated jurisdictions in which the Company's regulated businesses provide service have requested the Company furnish plans for the effect of the reduced corporate tax rate, which may impact the Company's rates to customers. Therefore, the Company has reserved for such impacts as an offset to revenue in certain jurisdictions. The Company will continue to make changes to reserve balances as new information becomes available. For more information on the details and statuses of the open requests, see Note 16.
Effective January 1, 2018, the Company adopted the requirements of the revenue from contracts with customers guidance following the modified retrospective method, as discussed in Notes 6 and 8. As such, results for reporting periods beginning January 1, 2018, are presented under the new guidance, while prior period amounts are not adjusted and continue to be reported in accordance with the historic accounting for revenue recognition. Based on the Company's analysis, the Company did not identify a significant change in the timing of revenue recognition under the new guidance as compared to the historic accounting for revenue recognition.
Certain prior year amounts have been reclassified to conform to the current year presentation in the consolidated financial statements related to the retrospective adoption of the FASB guidance to improve the presentation of net periodic pension and net periodic postretirement benefit costs, which was effective on January 1, 2018. The components of net periodic pension and postretirement costs, other than service costs, were reclassified from operating expenses to other income on the Consolidated Statements of Income, as discussed in Note 6.
The assets and liabilities for the Company's discontinued operations have been classified as held for sale and the results of operations are shown in income (loss) from discontinued operations, other than certain general and administrative costs and interest expense which do not meet the criteria for income (loss) from discontinued operations. At the time the assets were classified as held for sale, depreciation, depletion and amortization expense was no longer recorded. Unless otherwise indicated, the amounts presented in the accompanying notes to the consolidated financial statements relate to the Company's continuing operations. For more information on the Company's discontinued operations, see Note 10.

11



Note 2 - Seasonality of operations
Some of the Company's operations are highly seasonal and revenues from, and certain expenses for, such operations may fluctuate significantly among quarterly periods. Accordingly, the interim results for particular businesses, and for the Company as a whole, may not be indicative of results for the full fiscal year.
Note 3 - Accounts receivable and allowance for doubtful accounts
Accounts receivable consist primarily of trade receivables from the sale of goods and services which are recorded at the invoiced amount net of allowance for doubtful accounts, and costs and estimated earnings in excess of billings on uncompleted contracts. The total balance of receivables past due 90 days or more was $29.2 million, $27.2 million and $34.7 million at September 30, 2018 and 2017, and December 31, 2017, respectively.
The allowance for doubtful accounts is determined through a review of past due balances and other specific account data. Account balances are written off when management determines the amounts to be uncollectible. The Company's allowance for doubtful accounts at September 30, 2018 and 2017, and December 31, 2017, was $7.3 million, $9.0 million and $8.1 million, respectively.
Note 4 - Inventories and natural gas in storage
Natural gas in storage for the Company's regulated operations is generally carried at lower of cost or net realizable value, or cost using the last-in, first-out method. All other inventories are stated at the lower of cost or net realizable value. The portion of the cost of natural gas in storage expected to be used within one year was included in inventories. Inventories on the Consolidated Balance Sheets were as follows:
 
September 30, 2018

September 30, 2017

December 31, 2017

 
(In thousands)
Aggregates held for resale
$
133,477

$
116,399

$
115,268

Asphalt oil
40,781

26,682

30,360

Natural gas in storage (current)
29,084

29,974

20,950

Materials and supplies