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

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Reference 2: 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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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		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Beginning Balance / Day One Impact of adopting ASC 326	$ 5,000	$ 1,000	$ 0	$ 1,000
Provision for Credit Losses (less than $1 million for 3 months ended September 30, 2021)	1,000	1,000	6,000	1,000
Ending Balance	6,000	1,000	6,000	1,000
Accrued interest receivable and other assets \| Held-to-maturity Securities
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Accrued interest receivable	179,000		179,000		$ 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			0
Ending Balance	1,000		1,000
Corporate bonds
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Ending Balance	$ 5,000		$ 5,000
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		$ 1,000		$ 1,000