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Federal Home Loan Bank Stock With Other-Than-Temporary Impairment

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Securities Transferred, Unrealized Loss, Net Of Tax

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Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Indicates line item in statement of financial position that includes accrued interest, after 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 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 gain (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 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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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 excluding accrued interest, of investment in debt security measured at amortized cost (held-to-maturity) on nonaccrual status.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI) and investment in equity security without readily determinable fair value.

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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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Securities - Narrative (Details)	3 Months Ended		9 Months Ended		12 Months Ended
Securities - Narrative (Details)	Sep. 30, 2026 USD ($) debt_security	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($) debt_security	Sep. 30, 2025 USD ($)	Dec. 31, 2025 USD ($) debt_security
Schedule of Investments [Line Items]
Transferred Securities, Unrealized Loss, Before Tax	$ 89,900,000		$ 89,900,000		$ 96,600,000
Securities transferred, Unrealized Loss, Net of Tax	71,000,000.0		71,000,000.0		76,300,000
Fair value of securities transferred from AFS to HTM			0		0
Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract]
Realized net loss on sale of securities	0	$ 24,395,000	0	$ 24,949,000
Net realized losses on AFS securities				(25,400,000)
Gross realized gains on AFS securities				2,000,000.0
Proceeds from sale of AFS securities			0	411,502,000
Equity investments	9,337,000		9,337,000		$ 9,574,000
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
FHLB stock with other-than-temporary impairment	$ 0		$ 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| debt_security	353		353		161
Less: Net gains recognized during the period on equity investments sold during the period	$ 0	$ 0	$ 0	0
Debt Securities, Available-for-Sale, Accrued Interest	8,800,000		8,800,000		$ 9,400,000
Debt Securities, Held-to-Maturity, Accrued Interest	7,400,000		7,400,000		12,700,000
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, Nonaccrual	0		0		0
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	1,207,519,000		1,207,519,000		1,247,502,000
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0		0		0
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Excluding Accrued Interest	$ 24,000		$ 24,000		25,000
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Interest receivable		Interest receivable
State and political subdivisions
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	$ 1,044,582,000		$ 1,044,582,000		1,042,986,000
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0		0		0
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Excluding Accrued Interest	24,000		24,000		25,000
Corporate bonds and other
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	83,495,000		83,495,000		98,609,000
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0		0		0
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Excluding Accrued Interest	0		0		0
Collateralized Mortgage-Backed Securities and Municipal Securities
Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract]
Net realized losses on AFS securities				$ (1,500,000)
Asset Pledged as Collateral
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities	2,260,000,000		2,260,000,000		1,940,000,000
Asset Pledged As Collateral, Excess Amount
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities	12,900,000		12,900,000		241,800,000
Financial Asset, Past Due
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	$ 0		$ 0		$ 0