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Other-than-temporarily impaired equity investments

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Securities Transferred From Available for Sale to Held to Maturity

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Securities Transferred, Unrealized Loss, Net Of Tax

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Transferred Securities, Unrealized Loss, Before 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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Amount 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 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 credit loss expense (reversal of expense) on investment in debt security measured at amortized cost (held-to-maturity).

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

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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The cash inflow associated with the sale of securities that had been designated as held-to-maturity. Excludes proceeds from maturities, prepayments and calls by the issuer.

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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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Securities - Narrative (Details)	3 Months Ended		9 Months Ended		12 Months Ended
Securities - Narrative (Details)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 0		$ 0		$ 0
Transferred Securities, Unrealized Loss, Before Tax	96,200,000		96,200,000		1,500,000
Securities transferred, Unrealized Loss, Net of Tax	76,000,000		76,000,000		1,200,000
Fair value of securities transferred from AFS to HTM			1,070,000,000.00		0
Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract]
Net gain (loss) on sale of securities AFS	(99,000)	$ 1,381,000	(3,819,000)	$ 3,399,000
Gross realized gains on AFS securities			584,000	3,500,000
Gross realized losses on AFS securities			4,400,000	71,000
Equity investments	11,052,000		11,052,000		11,841,000
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Sale of HTM portfolio			0	0
Interest receivable	32,914,000		32,914,000		39,145,000
Debt Securities, Held-to-maturity, Nonaccrual	0		0		0
FHLB stock with other-than-temporary impairment	0		0
Other-than-temporarily impaired equity investments	$ 0		$ 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	811		811
State and political subdivisions
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, Credit Loss Expense (Reversal)	$ 0	0	$ 0	0
Corporate bonds and other
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, Credit Loss Expense (Reversal)	0	$ 0	0	$ 0
Asset Pledged as Collateral
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities	1,580,000,000		1,580,000,000		1,610,000,000
Financial Asset, Past Due
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Securities held to maturity (estimated fair value of $138,879)	0		0		0
Available-for-sale Securities
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Interest receivable	11,800,000		11,800,000		25,600,000
Held-to-maturity Securities
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Interest receivable	$ 6,300,000		$ 6,300,000		$ 244,000