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Debt Securities Available-for-Sale - Narrative (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022 USD ($) security loan	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) security loan	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, restricted	$ 581,600		$ 581,600		$ 522,100
Proceeds from sales and calls of debt securities available-for-sale	0	$ 89,600	41,464	$ 95,472
Debt securities, available-for-sale, realized gain (loss)	0
Debt securities, available-for-sale, realized gain		509	264	606
Debt securities, available-for-sale, realized loss		0	0	0
Debt securities, trading, realized gain (loss)	(1,600)	$ 807	(2,400)	$ 1,200
Debt securities available-for-sale, allowance for credit loss	0		0		0
Accrued interest receivable associated with debt securities available-for-sale	$ 2,600		$ 2,600		$ 2,500
Real Estate Mortgage Investment Conduits (REMICs) | GSE
Debt Securities, Available-for-sale [Line Items]
Number of debt securities, unrealized loss position longer than 12 months | loan	1		1
Number of debt securities, unrealized loss position less than 12 months | security	4		4
Real Estate Mortgage Investment Conduits (REMICs) | GSE | Pass Through
Debt Securities, Available-for-sale [Line Items]
Number of debt securities, unrealized loss position longer than 12 months | security	15		15
Number of debt securities, unrealized loss position less than 12 months | security	89		89
Real Estate Mortgage Investment Conduits (REMICs) | GSE | Non Pass Through
Debt Securities, Available-for-sale [Line Items]
Number of debt securities, unrealized loss position longer than 12 months | loan	26		26
Number of debt securities, unrealized loss position less than 12 months | security	61		61
Real Estate Mortgage Investment Conduits (REMICs) | Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Number of debt securities, unrealized loss position longer than 12 months | loan	2		2
Number of debt securities, unrealized loss position less than 12 months | security	26		26

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Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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