Debt Securities Available for Sale - Narrative (Details)	3 Months Ended
Mar. 31, 2024 USD ($) security	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities and collateralized mortgage obligations	$ 1,018,854,000
Mortgage-backed securities and collateralized mortgage obligations	869,217,000
Proceeds from sales of debt securities available for sale	3,495,000	$ 42,625,000
Gross gains on sale of available-for-sale securities	0	0
Gross losses on sale of available-for-sale securities	1,300,000	1,300,000
Proceeds from maturities and calls of debt securities, available-for-sale	$ 0	$ 0
Number of matured debt securities available -for-sale \| security	1
Proceeds from maturities of debt securities, available-for-sale	$ 10,000,000
Debt securities, available-for-sale, restricted	$ 224,900,000		$ 211,500,000
Number of securities in unrealized loss position \| security	349		329
Debt securities available for sale, at fair value	$ 1,187,440,000		$ 1,093,557,000
Accrued interest receivable on debt securities available for sale	4,800,000		3,700,000
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Debt securities available for sale, at fair value	78,481,000		77,769,000
Non-investment grade \| Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Debt securities available for sale, at fair value	8,100,000		8,100,000
Subsidiaries
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, restricted	$ 66,000,000		$ 75,100,000

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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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