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Debt Securities Available-for-Sale - Narrative (Details)	3 Months Ended
	Mar. 31, 2026 USD ($) loan security	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, restricted	$ 704,000,000.0		$ 686,300,000
Proceeds from sale of debt securities available-for-sale	0	$ 0
Debt securities, available-for-sale, realized gain	0	0
Debt securities, available-for-sale, realized loss	2,000	0
Debt securities, trading, realized (loss) gain	254,000	$ 299,000
Debt securities available-for-sale, allowance for credit loss	0		0
Accrued interest receivable associated with debt securities available-for-sale	$ 4,100,000		$ 4,200,000
Debt securities, available-for-sale, accrued interest, after allowance for credit loss, statement of financial position [extensible enumeration]	Accrued interest receivable		Accrued interest receivable
GSE
Debt Securities, Available-for-sale [Line Items]
Number of debt securities, unrealized loss position longer than 12 months \| loan	1
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Number of debt securities, unrealized loss position longer than 12 months \| loan	1
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Number of debt securities, unrealized loss position longer than 12 months \| loan	1
Pass through \| GSE
Debt Securities, Available-for-sale [Line Items]
Number of debt securities \| security	90
Number of debt securities, unrealized loss position less than 12 months \| security	14
Non pass through \| REMICs:
Debt Securities, Available-for-sale [Line Items]
Number of debt securities, unrealized loss position longer than 12 months \| loan	61
Number of debt securities, unrealized loss position less than 12 months \| loan	3