Debt Securities - Narrative (Details)	12 Months Ended
Dec. 31, 2022 USD ($) security	Dec. 31, 2021 USD ($)
Summary of debt securities
Debt securities, available-for-sale	$ 5,307,307,000	$ 9,170,849,000
Severity rate on available-for-sale debt securities in an unrealized loss position	5.00%
Number of credit rating categories, highest \| security	4
Interest receivable, available-for-sale debt securities	$ 10,518,000	18,788,000
ACL on available-for-sale debt securities	0
Interest receivable, held-to-maturity debt securities	17,524,000	8,737,000
ACL on held-to-maturity debt securities	0	0
Asset Pledged as Collateral \| FHLB, FRB, securities sold under agreements to repurchase, and deposits
Summary of debt securities
Debt securities, available-for-sale	2,768,229,000	2,687,652,000
Financial Asset, Past Due
Summary of debt securities
Debt securities, available-for-sale	0	0
Debt securities, held-to-maturity	$ 0	$ 0

Available-for-sale, Securities in Unrealized Loss Positions, Severity Rate

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Carrying amount as of the balance sheet date of interest earned but not received on available-for-sale debt securities.

+ References

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Carrying amount as of the balance sheet date of interest earned but not received on held-to-maturity debt securities.

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Number of credit rating categories, highest

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

+ References

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-Publisher FASB
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Amount excluding accrued interest, 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 allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

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Amount excluding accrued interest, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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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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