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Individually Evaluated for Impairment Financing Receivable, Individually Evaluated for Impairment Interest on Deposits Interest Expense, Deposits Other Noninterest Income From Contracts With Customers Other Noninterest Income From Contracts With Customers Other Noninterest Income From Contracts With Customers Idaho [Member] IDAHO Commercial Real Estate [Member] Commercial Real Estate [Member] Commercial and Industrial Sector [Member] Commercial and Industrial Sector [Member] Stockholders' Equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Other Service Charges Other Service Charges Other Service Charges Loans and Leases Receivable, before Fees, Gross Loans and Leases Receivable, before Fees, Gross Occupancy, Net Occupancy, Net Deferred commitment fees Liability for guarantees-defered commitment fees Liability for guarantees-defered commitment fees Debt Instruments [Abstract] Segments [Axis] Segments [Axis] Financing Receivable, Allowance for Credit 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Receivable Recorded Investmetn With Allowance [Member] Summary Of Past Due Loans (Accruing And Nonaccruing) Financing Receivable, Past Due [Table Text Block] Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Table] Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Table] California Bank Trust [Member] California Bank Trust [Member] California Bank & Trust [Member] Debt Security Category [Axis] Debt Security Category [Axis] Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Net cash provided by (used in) operating activities Net Cash Provided by (Used in) Operating Activities Underlying Asset Class [Domain] Underlying Asset Class [Domain] Series H 5.75% Non-Cumulative Perpetual Preferred Stock [Member] Series H 5.75% Non-Cumulative Perpetual Preferred 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Unrealized Loss Position, Fair Value Capitalization, Long-term Debt and Equity [Abstract] Net Income (Loss) Available to Common Stockholders, Diluted Net Income (Loss) Available to Common Stockholders, Diluted TEXAS TEXAS Number of AFS investment securities in an unrealized loss position Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions Collateral [Axis] Collateral [Axis] allowance for loan losses by impairment [Table Text Block] allowance for loan losses by impairment [Table Text Block] allowance for loan losses by impairment [Table Text Block] Schedule of Financing Receivable, Troubled Debt Restructurings [Table] Financing Receivable, Troubled Debt Restructuring [Table] Proceeds from (Payments for) Other Financing Activities Proceeds from (Payments for) Other Financing Activities Liabilities Liabilities Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities 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