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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at amortized cost (held-to-maturity).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Investment Securities - Allowance for Credit Losses for HTM Securities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Beginning Balance / Day One Impact of adopting ASC 326	$ 392
Provision for Credit Losses	720	$ 56
Ending Balance	1,112	230
Accrued interest receivable and other assets \| Held-to-maturity Securities
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Accrued interest receivable	96,100		$ 55,000
Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Beginning Balance / Day One Impact of adopting ASC 326	392	0
Provision for Credit Losses	139	56
Ending Balance	531	230
Corporate bonds
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Beginning Balance / Day One Impact of adopting ASC 326	0
Provision for Credit Losses	581
Ending Balance	$ 581
Cumulative adjustment for the adoption of amendment
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Beginning Balance / Day One Impact of adopting ASC 326		174
Cumulative adjustment for the adoption of amendment \| Municipal bonds and notes
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Beginning Balance / Day One Impact of adopting ASC 326		$ 174