Debt Securities Available for Sale - Narrative (Details)	3 Months Ended
Mar. 31, 2023 USD ($) security	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities and collateralized mortgage obligations	$ 1,324,035,000
Mortgage-backed securities and collateralized mortgage obligations	1,170,873,000
Proceeds from sales of debt securities available for sale	42,625,000	$ 0
Gross gains on sale of available-for-sale securities	0
Gross losses on sale of available-for-sale securities	1,300,000
Proceeds from maturities and calls of debt securities, available-for-sale	0
Sale and maturity of debt securities, available-for-sale		$ 0
Debt securities, available-for-sale, restricted	$ 990,900,000		$ 724,000,000
Number of securities in unrealized loss position \| security	439		455
Accrued interest receivable on debt securities available for sale	$ 3,300,000		$ 3,200,000
Subsidiaries
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, restricted	$ 39,000,000		$ 28,300,000

Proceeds From Maturities And Calls Of Debt Securities, Available-for-Sale

No definition available.

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- Definition

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.

+ References

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Fair value 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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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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Amount of realized gain 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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Amount of realized loss 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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Amount of restricted 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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of cash inflow from sale, maturity, prepayment and call of 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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Amount of cash inflow from sale of 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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