Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Summary of Significant Accounting Policies Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Held to maturity allowance for credit loss	$ (67)	$ 61
Retained Earnings (Accumulated Deficit)	2,458,920		$ 2,380,867
Cumulative effect of ASU 2016-13 adoption (CECL)	47,776		21,907
Financing Receivable, Allowance for Credit Loss			201,371
Cumulative Effect, Period of Adoption, Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		131,147
Allowance for Loan Losses [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss	383,702		201,371
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of ASU 2016-13 adoption (CECL)	47,776		$ 21,907
Accounting Standards Update 2016-13 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained Earnings (Accumulated Deficit)		98,000
Deferred Income Tax Assets, Net		33,000
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of ASU 2016-13 adoption (CECL)		18,690
Accounting Standards Update 2016-13 [Member] \| Allowance for Loan Losses [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss	112,457	112,000
Accounting Standards Update 2016-13 [Member] \| SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of ASU 2016-13 adoption (CECL)	$ 18,690	19,000
Accounting Standards Update 2016-13 [Member] \| Allowance for Loans Losses and Unfunded Commitments [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		$ 131,000