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 of deferred tax asset attributable to deductible temporary differences and carryforwards.

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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 Schedule of Impact of Adoption of New Accounting Standard (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Financing receivable, allowance for credit loss		$ 43,288
Allowance for credit losses on held-to-maturity debt securities	$ (645)	0
Deferred tax asset		14,851
Retained earnings	$ 393,900	380,737	$ 380,737
Loans Receivable
Financing Receivable, Credit Quality Indicator [Line Items]
Financing receivable, allowance for credit loss		5,314,337
Unfunded Loan Commitment
Financing Receivable, Credit Quality Indicator [Line Items]
Reserve for unfunded commitments		430
Cumulative Effect, Period Of Adoption, Adjustment
Financing Receivable, Credit Quality Indicator [Line Items]
Financing receivable, allowance for credit loss		28,387
Allowance for credit losses on held-to-maturity debt securities		303
Deferred tax asset		5,898
Retained earnings		(18,114)
Cumulative Effect, Period Of Adoption, Adjustment \| Loans Receivable
Financing Receivable, Credit Quality Indicator [Line Items]
Financing receivable, allowance for credit loss		7,091
Cumulative Effect, Period Of Adoption, Adjustment \| Unfunded Loan Commitment
Financing Receivable, Credit Quality Indicator [Line Items]
Reserve for unfunded commitments		2,413
Cumulative Effect, Period Of Adoption, Adjusted Balance
Financing Receivable, Credit Quality Indicator [Line Items]
Financing receivable, allowance for credit loss		71,675
Allowance for credit losses on held-to-maturity debt securities		303
Deferred tax asset		20,749
Retained earnings		362,623
Cumulative Effect, Period Of Adoption, Adjusted Balance \| Loans Receivable
Financing Receivable, Credit Quality Indicator [Line Items]
Financing receivable, allowance for credit loss		5,321,428
Cumulative Effect, Period Of Adoption, Adjusted Balance \| Unfunded Loan Commitment
Financing Receivable, Credit Quality Indicator [Line Items]
Reserve for unfunded commitments		2,843
Accounting Standards Update 2016-13 \| Cumulative Effect, Period Of Adoption, Adjustment
Financing Receivable, Credit Quality Indicator [Line Items]
Retained earnings		$ 18,100