Other Debt - Additional Information (Details) - USD ($)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Federal Home Loan Bank of Des Moines Advances	$ 550,000,000
Federal Reserve Bank Advances
Debt Instrument [Line Items]
Undrawn line of credit with the FHLB or FRB	7,400,000,000
Federal Home Loan Bank Advance
Debt Instrument [Line Items]
Undrawn line of credit with the FHLB or FRB	1,700,000,000
Federal Home Loan Bank of Des Moines Advances	$ 550,000,000	$ 550,000,000
Weighted average interest rate	4.13%
Federal Home Loan Bank Advance \| Maturity Start Year
Debt Instrument [Line Items]
Maturity year	2026
Federal Home Loan Bank Advance \| Maturity End Year
Debt Instrument [Line Items]
Maturity year	2028
Finance Lease Obligations
Debt Instrument [Line Items]
Lease term (in years)	60 years

Debt instruments maturity year.

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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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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Weighted average interest rate of debt outstanding.

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Term of lessee's finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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