Number of Securities in an Unrealized Loss Position

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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).

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

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on investment in debt security measured at amortized cost (held-to-maturity).

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Amount of cash outflow to acquire 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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- Definition

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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Debt and Equity Securities - Narrative (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2026 USD ($) security	Sep. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
Debt Securities, Available-for-sale [Line Items]
Payments to acquire AFS securities, debt	$ 877,772	$ 843,190
Number of securities in an unrealized loss position \| security	92
Expected loss on held-to-maturity securities	$ 0
Allowance for credit losses on available-for-sale debt securities	0		$ 0
Allowance for credit losses on held-to-maturity debt securities	$ 0		0
Collateralized Mortgage-Backed Securities
Debt Securities, Available-for-sale [Line Items]
Number of securities in an unrealized loss position \| security	83
Credit risk transfer securities
Debt Securities, Available-for-sale [Line Items]
Number of securities in an unrealized loss position \| security	2
Deposits
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities pledged to secure certain customer repurchase agreements and deposits	$ 820		$ 937
Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities in an unrealized loss position \| security	7