Borrowings - Narrative (Details) $ in Thousands	3 Months Ended
Mar. 31, 2026 USD ($) advance	Dec. 31, 2025 USD ($) advance
Federal Home Loan Bank, Advances [Line Items]
Number of advances \| advance	33	34
Borrowings	$ 1,427,500	$ 1,420,000
Weighted average interest rate	3.92%	3.91%
Collateralized amount	$ 4,200,000	$ 4,000,000
Revolving Credit Facility \| Overnight Borrowing Lines \| Line of Credit
Federal Home Loan Bank, Advances [Line Items]
Short-term debt	180,000	0
Revolving Credit Facility \| Line of Credit
Federal Home Loan Bank, Advances [Line Items]
Maximum borrowing capacity	$ 100,000
Interest rate, variable	4.02%
Short-term debt	$ 24,000	0
Line of Credit \| Unsecured Debt
Federal Home Loan Bank, Advances [Line Items]
Maximum borrowing capacity	20,000
Borrowings	$ 0	$ 17,000
Fixed interest rate	7.16%	7.37%
Federal Home Loan Bank, Advances, Putable Option
Federal Home Loan Bank, Advances [Line Items]
Borrowings	$ 0	$ 10,000
Minimum
Federal Home Loan Bank, Advances [Line Items]
Fixed interest rate	2.90%	1.04%
Scheduled maturities	1 month	1 month
Maximum
Federal Home Loan Bank, Advances [Line Items]
Fixed interest rate	4.84%	4.84%
Scheduled maturities	7 years 9 months 18 days	8 years 2 months 12 days

Federal Home Loan Bank, Number Of Advances

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount of assets pledged to secure a debt instrument.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The calculated weighted average interest rate for Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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