Investment Securities - Additional Information (Details)	3 Months Ended			6 Months Ended
	Jun. 30, 2023 USD ($) position	Mar. 31, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) position	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($) position
Investments, Debt and Equity Securities [Abstract]
Equity securities	$ 61,010,000			$ 61,010,000		$ 48,731,000
Trading debt securities	3,409,000			3,409,000		$ 13,438,000
Debt securities, trading, realized gain	$ 226,000			$ 628,000
Debt securities, trading, realized loss			$ 387,000		$ 1,400,000
Number of security positions in the debt securities available for sale portfolio in an unrealized loss position | position	725			725		730
Fair value of debt securities available for sale pledged as collateral	$ 847,100,000			$ 847,100,000
Weighted-average remaining expected life of residential mortgage-backed securities available for sale, years				7 years 8 months 4 days
Provision for credit losses		$ 5,000,000		$ 5,000,000
Impairment loss			$ 0		$ 0
Accrued interest on investments available for sale	4,900,000			4,900,000		$ 5,600,000
Accrued interest on securities held to maturity	$ 13,600,000			$ 13,600,000		$ 13,500,000
Number of security positions in the securities held to maturity portfolio in an unrealized loss position | position	811			811		802
Fair value of investments held to maturity pledged as collateral	$ 2,400,000,000			$ 2,400,000,000
Weighted-average remaining expected life of residential mortgage-backed securities held to maturity, years				10 years 18 days