Debt Securities Available for Sale - Narrative (Details)	12 Months Ended
Dec. 31, 2023 USD ($) security	Dec. 31, 2022 USD ($) security	Dec. 31, 2021 USD ($)
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities and collateralized mortgage obligations, amortized cost	$ 1,009,508,000
Mortgage-backed securities and collateralized mortgage obligations, fair value	867,585,000
Proceeds from sales of debt securities available for sale	277,022,000	$ 126,772,000	$ 90,339,000
Debt securities, available-for-sale securities, gross realized gains	0	710,000	2,100,000
Debt securities, available-for-sale, realized loss	10,800,000	500,000	439,000
Proceeds from calls of debt securities available for sale	0	0	14,000,000
Proceeds from maturities of debt securities, available-for-sale	4,000	915,000	210,000
Calls of debt securities, available-for-sale, unrealized loss			$ 0
Debt securities, available-for-sale, restricted	$ 211,500,000	$ 724,000,000
Number of unrealized loss positions \| security	329	455
Debt securities available for sale, at fair value	$ 1,093,557,000	$ 1,328,634,000
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Accrued interest receivable
Accrued interest receivable on debt securities available for sale	$ 3,700,000	3,200,000
Subsidiaries
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, restricted	75,100,000	28,300,000
Mortgage-backed securities and collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Debt securities available for sale, at fair value	867,585,000	1,181,727,000
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Debt securities available for sale, at fair value	$ 77,769,000	$ 79,766,000
Corporate debt securities \| External Credit Rating, Non Investment Grade
Debt Securities, Available-for-sale [Line Items]
Number of temporarily impaired securities \| security	2
Debt securities available for sale, at fair value	$ 8,100,000

Calls Of Debt Securities, Available-for-sale, Unrealized Loss

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Number Of Temporarily Impaired Securities

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping.

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