Securities (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities transferred to Held-to-Maturity	$ 1,059,737,000	$ 0	$ 873,613,000	$ 179,800,000
Unrealized after tax gain (loss) on available-for-sale securities transferred to the held-to-maturity portfolio	1,500,000		(69,000,000)	$ 2,200,000
Allowance for credit losses - securities held-to-maturity	(1,608,000)	(161,000)
Securities Loaned and Securities Sold under Agreement to Repurchase, Gross Including Not Subject to Master Netting Arrangement	194,900,000
Proceeds from Sale of Debt Securities, Available-for-sale	29,501,000	37,457,000	145,631,000
Debt Securities, Available-for-sale, Realized Gain	292,000	769,000	2,200,000
Debt Securities, Available-for-sale, Realized Loss	136,000	10,000	$ 1,200,000
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	325,426,000	33,386,000
Debt Securities, Available-for-sale, Unrealized Loss Position	3,007,832,000	$ 2,263,824,000
Securities pledged as collateral
Debt Securities, Available-for-sale [Line Items]
Financial Instruments, Owned, at Fair Value	724,000,000
Securities pledged as collateral
Debt Securities, Available-for-sale [Line Items]
Securities Loaned and Securities Sold under Agreement to Repurchase, Gross Including Not Subject to Master Netting Arrangement	$ 194,900,000