Debt Disclosure [Abstract] Composition of Notes Payable Schedule of Debt [Table Text Block] Future Annual Minimum Principal Payments of Notes Payable Schedule of Maturities of Long-term Debt [Table Text Block] Commitments and Contingencies Disclosure [Abstract] COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock Common Stock [Member] Additional Paid-in Capital Additional Paid-in Capital [Member] Accumulated Other Comprehensive Gain (Loss) AOCI Attributable to Parent [Member] Accumulated Deficit Retained Earnings [Member] Sale of Stock [Axis] Sale of Stock [Axis] Sale of Stock [Domain] Sale of Stock [Domain] Public offering Public Offering [Member] Public Offering [Member] At-the-market At-the-market Offering [Member] At-the-market Offering [Member] 2018 Stock purchase agreement 2018 Stock Purchase Agreement [Member] 2018 Stock Purchase Agreement [Member] 2019 Stock purchase agreement 2019 Stock Purchase Agrrement [Member] 2019 Stock Purchase Agreement [Member] Statement [Line Items] Statement [Line Items] Stockholders’ deficit Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance (in shares) Common Stock, Shares, Outstanding Beginning balance Stockholders' Equity Attributable to Parent Issuance of common stock, net of issuance cost (in shares) Stock Issued During Period, Shares, New Issues Issuance of common stock, net of issuance cost Stock Issued During Period, Value, New Issues Shares issued for cash upon the exercise of stock options (in shares) Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Shares issued for cash upon the exercise of stock options Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Issuance of common stock for cash under employee stock purchase plan (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Issuance of common stock for cash under employee stock purchase plan Stock Issued During Period, Value, Employee Stock Purchase Plan Share-based compensation expense APIC, Share-based Payment Arrangement, Increase for Cost Recognition Reclassification of warrant liability from equity Warrants, Reclassification Of Warrant Liability From Equity Warrants, Reclassification Of Warrant Liability From Equity Change in unrealized gain on investments Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, before Tax Net loss Net Income (Loss) Attributable to Parent Ending balance (in shares) Ending balance Organization, Consolidation and Presentation of Financial Statements [Abstract] Accumulated deficit Retained Earnings (Accumulated Deficit) Cash, cash equivalents and short-term investments Cash, Cash Equivalents, and Short-term Investments Commitments and Contingencies [Table] Commitments and Contingencies [Table] Commitments and Contingencies [Table] Title of Individual [Axis] Title of Individual [Axis] Title of Individual [Domain] Title of Individual [Domain] Chief Executive Officer Chief Executive Officer [Member] Statistical Measurement [Axis] Statistical Measurement [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Counterparty Name [Axis] Counterparty Name [Axis] Counterparty Name [Domain] Counterparty Name [Domain] University of Texas University of Texas [Member] University of Texas [Member] RICC Roche Innovation Center Copenhagen A/S [Member] Roche Innovation Center Copenhagen A/S [Member] t2cure t2cure GmbH [Member] t2cure GmbH [Member] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] United States UNITED STATES Other Regions Non-US [Member] European Union or Japan European Union or Japan [Member] European Union or Japan [Member] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Yale University Yale University [Member] Yale University [Member] Commitments and Contingencies [Line Items] Commitments and Contingencies [Line Items] [Line Items] for Commitments and Contingencies [Table] Term of employee's base salary Employment Agreement, Total Compensation Due To Termination For Good Reason Or Resignation, In Base Salary Term Employment Agreement, Total Compensation Due To Termination For Good Reason Or Resignation, In Base Salary Term Term of executive’s outstanding unvested stock options Employment Agreement, Term Of Executive’s Outstanding Unvested Stock Options Employment Agreement, Term Of Executive’s Outstanding Unvested Stock Options Term of employee health coverage Employment Agreement, Term Of Employee Health Coverage Employment Agreement, Term Of Employee Health Coverage Resignation for good reason term Employment Agreement, Resignation For Good Reason Term Employment Agreement, Resignation For Good Reason Term Change on control term Employment Agreement, Change Of Control Term Employment Agreement, Change Of Control Term Total compensation due to change in control, in base salary term Employment Agreement, Total Compensation Due To Change In Control, In Base Salary Term Employment Agreement, Total Compensation Due To Change In Control, In Base Salary Term Number of arrangements Collaborative Arrangement, Number of Arrangements Collaborative Arrangement, Number of Arrangements Nonrefundable upfront license documentation fee License Costs, Upfront Licensing Fee Per License License Costs, Upfront Licensing Fee per License Annual license maintenance fee License Cost, Annual Maintenance Fee Per License License Cost, Annual Maintenance Fee per License Potential milestone payment for initiation of defined clinical trials (up to) License Costs, Potential Milestone Payment, Initiation Of Defined Clinical Trials License Costs, Potential Milestone Payment, 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Renewal Terms Lessee, Operating Lease, Number Of Renewal Terms Renewal term Lessee, Operating Lease, Renewal Term Rent expense Operating Leases, Rent Expense Rent expense Operating Lease, Cost Operating expenses of leases Operating Leases, Operating Expense Operating Leases, Operating Expense Future annual minimum payment 2020 Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months Income Tax Disclosure [Abstract] Federal statutory income tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Federal and state tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Percent State income taxes, net of federal benefit Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Change in valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Other permanent items Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Change in tax rate Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Other, net Effective Income Tax Rate Reconciliation,Other Reconciling Items, Percent Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Components of Collaboration Revenue Disaggregation of Revenue [Table Text Block] Other Liabilities Disclosure [Abstract] Class of Warrant or Right [Table] Class of Warrant or Right [Table] Class of Warrant or Right [Axis] Class of Warrant or Right [Axis] Class of Warrant or Right [Domain] Class of Warrant or Right [Domain] Warrants to purchase Common Stock Common Stock Warrants [Member] Common Stock Warrants [Member] Class of Warrant or Right [Line Items] Class of Warrant or Right [Line Items] Number Class of Warrant or Right, Activity [Roll Forward] Class of Warrant or Right, Activity [Roll Forward] Beginning balance (in shares) Class of Warrant or Right, Outstanding Expiries (in shares) Class Of Warrant Or Right Expired In Period Class Of 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[Member] SVB Loan Agreement 2017 [Member] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Notes Payable to Banks Notes Payable to Banks [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Proceeds from debt Proceeds from Issuance of Debt Repayment period Debt Instrument, Term Interest-only period Debt Instrument, Term, Interest Only Payments Debt Instrument, Term, Interest Only Payments Interest rate at period end Line of Credit Facility, Interest Rate at Period End Final payment fee Debt Instrument, Final Payment Fee Debt Instrument, Final Payment Fee Interest margin in event of default Debt Instrument, Debt Default, Interest Margin Applicable Debt Instrument, Debt Default, Interest Margin Applicable Accounting Policies [Abstract] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent 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Collaborative Arrangement and Arrangement Other than Collaborative [Table] Collaborative Arrangement and Arrangement Other than Collaborative [Table] Collaborative Arrangement and Arrangement Other than Collaborative [Axis] Collaborative Arrangement and Arrangement Other than Collaborative [Axis] Collaborative Arrangement and Arrangement Other than Collaborative [Domain] Collaborative Arrangement and Arrangement Other than Collaborative [Domain] Servier Collaboration Agreement Collaborative Arrangement [Member] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Milestone payments Milestone Payments [Member] Milestone Payments [Member] Servier Servier [Member] Servier [Member] Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Maximum reimbursements of development costs Contract with Customer, Asset, before Allowance for Credit Loss Incremental increase in amount Collaborative Arrangement, Incremental Increase In Amount Collaborative Arrangement, Incremental Increase In Amount Development and regulatory milestones Collaborative Arrangement, Development And Regulatory Milestones Collaborative Arrangement, Development And Regulatory Milestones Total revenue Revenue from Contract with Customer, Including Assessed Tax Amounts incurred but not yet billed Contract With Customer, Asset, Incurred But Not Yet Billed Contract With Customer, Asset, Incurred But Not Yet Billed Accounts receivable Accounts Receivable, after Allowance for Credit Loss, Current Cover page. Document Type Document Type Document Period End Date Document Period End Date Entity Registrant Name Entity Registrant Name Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Entity Small Business Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Public Float Entity Public Float Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Central Index Key Entity Central Index Key Amendment Flag Amendment Flag Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Current Fiscal Year End Date Current Fiscal Year End Date Entity Shell Company Entity Shell Company 2020 Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months 2021 Long-term Debt, Maturities, Repayments of Principal in Year Two Total Long-term Debt Share-based Payment Arrangement [Abstract] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Research and development Research and Development Expense [Member] General and administrative General and Administrative Expense [Member] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Total share-based compensation expense Share-based Payment Arrangement, Expense Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Research and development reimbursable costs Reimbursement Revenue [Member] Reimbursement Revenue [Member] Collaboration revenue Collaboration Revenue [Member] Collaboration Revenue [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] NOTES PAYABLE Debt Disclosure [Text Block] Property, Plant and Equipment [Abstract] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Lab equipment Equipment [Member] Leasehold improvements Leasehold Improvements [Member] Computer hardware and software Computer Equipment [Member] Furniture and fixtures Furniture and Fixtures [Member] Property and equipment Property, Plant and Equipment, Gross Less: accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property and equipment, net Property, Plant and Equipment, Net INCOME TAXES Income Tax Disclosure [Text Block] Income Statement [Abstract] Grant revenue Grant [Member] Revenue: Revenues [Abstract] Operating expenses: Operating Expenses [Abstract] Research and development Research and Development Expense General and administrative General and Administrative Expense Total operating expenses Operating Expenses Loss from operations Operating Income (Loss) Other income (expense): Nonoperating Income (Expense) [Abstract] Interest and other income Nonoperating Income (Expense) Interest and other expense Interest and Debt Expense Net loss Change in unrealized gain (loss) on investments Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Net loss Net Income (Loss) Available to Common Stockholders, Basic Net loss per share, basic and diluted (in dollars per share) Earnings Per Share, Basic and Diluted Weighted-average shares used to compute basic and diluted net loss per share (in shares) Weighted Average Number of Shares Outstanding, Basic and Diluted WARRANTS Stockholders' 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payable, net of current portion Notes Payable, Noncurrent Other liabilities Other Liabilities, Noncurrent Total liabilities Liabilities Commitments and contingencies Commitments and Contingencies Stockholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] Common stock, $0.01 par value; 100,000,000 shares authorized; 34,861,876 and 30,839,463 shares issued and outstanding at December 31, 2019 and 2018, respectively Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Total stockholders’ equity Total liabilities and stockholders’ equity Liabilities and Equity Payables and Accruals [Abstract] Accrued outsourced clinical trials and preclinical studies Accrued Outsourcing Clinical and Pre-clinical Studies Accrued Outsourcing Clinical and Pre-clinical Studies Restructuring liability Restructuring Reserve Accrued employee compensation and related taxes Employee-related Liabilities, Current Accrued legal fees and expenses Accrued Legal Fees, Current Accrued Legal Fees, Current Accrued other professional service fees Accrued Professional Fees, Current Value of liability-classified stock purchase warrants Accrued Liability of Warrants on Temporary Equity Accrued Liability of Warrants on Temporary Equity Deferred and accrued facility lease obligations Accrued Rent, Current Accrued equipment and lab materials Accrued Liabilities, Equipment and Lab Materials Accrued Liabilities, Equipment and Lab Materials Other accrued liabilities Other Accrued Liabilities, Current Total accrued liabilities Restructuring and Related Activities [Abstract] Expected position eliminations Restructuring and Related Cost, Expected Number of Positions Eliminated Expected position eliminations, percent Restructuring and Related Cost, Number of Positions Eliminated, Period Percent Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Scenario [Axis] Scenario [Axis] Scenario [Domain] Scenario [Domain] Forecast Forecast [Member] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Restructuring charges Restructuring Charges Principal amount outstanding Long-term Debt, Gross Unamortized debt discount Debt Instrument, Unamortized Discount Accreted final payment fee Long-Term Debt, Accumulated Accretion Of Final Payment Fee Long-term Debt, Accumulated Accretion of Final Payment Fee Total note payable Notes Payable Less: current maturities Note payable, net of current portion NET LOSS PER SHARE Earnings Per Share [Text Block] Equity [Abstract] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Aspire Capital Fund,LLC Aspire Capital Fund,LLC [Member] Aspire Capital Fund,LLC [Member] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Aspire Stock Purchase Agreement Aspire Stock Purchase Agreement [Member] Aspire Stock Purchase Agreement [Member] LLS Stock Purchase Agreement LLS Stock Purchase 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Inc [Member] Oppenheimer & Co. 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Assets, Valuation Allowance Net deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Stock Option Activity Share-based Payment Arrangement, Option, Activity [Table Text Block] Fair Value Assumptions for Stock Options Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Allocation of Share-based Compensation Expense Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block] Summary of Restructuring Activity Restructuring and Related Costs [Table Text Block] Summary of Warrants Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block] Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text 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Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Accounts payable Increase (Decrease) in Accounts Payable Accrued and other liabilities Increase (Decrease) in Accrued Liabilities Net cash used in operating activities Net Cash Provided by (Used in) Operating Activities Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Purchases of short-term investments Payments to Acquire Marketable Securities Maturities of short-term investments Proceeds from Sale and Maturity of Marketable Securities Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Net cash provided by (used in) investing activities Net Cash Provided by (Used in) Investing Activities Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Payments of principal on note payable Repayments of Notes Payable Payment of issuance costs associated with the sale of common stock Payments of Stock Issuance Costs Proceeds from stock purchases under employee stock purchase plan Proceeds from Repayment of Loans by Employee Stock Ownership Plans Proceeds from the exercise of stock options Proceeds from Stock Options Exercised Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Net decrease in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Supplemental disclosure of cash flow information Supplemental Cash Flow Information [Abstract] Cash paid for interest Interest Paid, Excluding Capitalized Interest, Operating Activities Change in unrealized gain (loss) on investments Unrealized Gain (Loss) on Investments Supplemental disclosure of non-cash investing and financing activities Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Change in unrealized gain (loss) on investments Amortization of public offering costs Amortization Of Stock Issuance Costs Amortization Of Stock Issuance Costs CAPITAL STOCK Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2008 Equity Plan Equity Plan 2008 [Member] Equity Plan 2008 [Member] 2016 Equity Plan Equity Plan 2016 [Member] Equity Plan 2016 [Member] Non-employee Stock Option Non-employee Stock Option [Member] Non-employee Stock Option [Member] Vesting [Axis] Vesting [Axis] Vesting [Domain] Vesting [Domain] Initial vesting period Share-based Payment Arrangement, Tranche One [Member] Subsequent vesting period Share-based Payment Arrangement, Tranche Two [Member] Supplier [Axis] Supplier [Axis] Supplier [Domain] Supplier [Domain] Non-employees Non-employees [Member] Non-employees [Member] Shares outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Shares authorized for issuance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Basis for equity incentive plan (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Expiration period Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Percent of common stock authorized under plan Share-based Compensation Arrangement By Share-based Payment Award, Number Of Shares Authorized, Percent Of Common Stock Outstanding Share-based Compensation Arrangement By Share-based Payment Award, Number Of Shares Authorized, Percent Of Common Stock Outstanding Additional shares authorized for plan (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Outstanding, exercisable equity awards (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Awards Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Equity Awards Outstanding Remaining equity awards available for future issuances (in shares) Common Stock, Capital Shares Reserved for Future Issuance Vesting percent Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Vesting period (up to) Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Total intrinsic value of stock options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Cash received from exercise stock options Weighted average fair value per option (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Shares issued in period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Purchase price of common stock, percentage of fair market value Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent Stock purchase offering period Share-based Compensation Arrangement By Share-based Payment Award, Stock Plan Offering Period Share-based Compensation Arrangement By Share-based Payment Award, Stock Plan Offering Period Number of shares available for issuance under ESPP (in shares) Employee Stock Ownership Plan (ESOP), Number of Allocated Shares Unrecognized employee stock-based compensation costs Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Remaining weighted-average period for RSUs Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition ACCRUED LIABILITIES Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block] DESCRIPTION OF BUSINESS Business Description and Basis of Presentation [Text Block] Common stock, shares issued (in shares) Common Stock, Shares, Issued Common stock, shares outstanding (in shares) Number of Options (in thousands) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Beginning balance (in shares) Granted (in shares) Exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Forfeited or Expired (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Ending balance (in shares) Vested or expected to vest (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number Exercisable (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number Vested (in shares) Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Beginning balance (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Granted (in usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercised (in usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Forfeited or expired (in usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Ending balance (in usd per share) Vested or expected to vest (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price Exercisable (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price Vested (in usd per share) Weighted average remaining contractual term and Aggregate intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Outstanding (Weighted Average Remaining Contractual Term) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term Vested or expected to vest (Weighted Average Remaining Contractual Term) Outstanding (Aggregate Intrinsic Value) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value Vested or expected to vest (Aggregate Intrinsic Value) Exercisable (Weighted Average Remaining Contractual Term) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term Vested (Weighted Average Remaining Contractual Term) Exercisable (Aggregate Intrinsic Value) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value Vested (Aggregate Intrinsic Value) Schedule of Effective Income Tax Rate Reconciliation Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of Deferred Tax Assets and Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Components of Property and Equipment Property, Plant and Equipment [Table Text Block] Selected Quarterly Financial Data (Unaudited) Quarterly Financial Information [Table Text Block] RESTRUCTURING PLAN Restructuring and Related Activities Disclosure [Text Block] SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) Quarterly Financial Information [Text Block]