Securities - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2013
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities transferred to held-to-maturity securities					$ 12,700,000	$ 536,000,000
Unrealized net loss on securities reclassified from available-for-sale to held-to-maturity, Gross					209,000	$ 13,300,000
Debt securities, available-for-sale, realized gain (loss)	$ 131,000	$ 0	$ 23,000	$ 0
Debt securities, held to maturity	1,027,712,000		1,027,712,000		1,139,193,000
Equity investments	81,722,000		81,722,000		101,155,000
Federal Home Loan Bank Advances, Federal Reserve Discount Window And Other Borrowings
Debt Securities, Available-for-sale [Line Items]
Debt securities, held to maturity	866,500,000		866,500,000		1,140,000,000
Securities Sold under Agreements to Repurchase
Debt Securities, Available-for-sale [Line Items]
Debt securities, held to maturity	105,500,000		105,500,000		$ 142,900,000
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	56,000,000		56,000,000
Debt securities, fair value	52,700,000		52,700,000
State, municipal and sovereign debt obligations
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	75,000,000		75,000,000
Debt securities, fair value	68,700,000		68,700,000
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	296,200,000		296,200,000
Debt securities, fair value	$ 274,900,000		$ 274,900,000