Allowance for Credit Losses and Credit Quality of Loans, Allowance for Credit Losses by Portfolio Segments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Activity in allowance for credit losses by portfolio segment [Roll Forward]
Balance, beginning of period	$ 90,000	$ 105,000	$ 92,000	$ 110,000
Charge-offs	(4,046)	(4,009)	(8,537)	(8,669)
Recoveries	3,256	2,725	5,151	5,181
Provision	4,390	(5,216)	4,986	(8,012)
Balance, end of period	93,600	98,500	93,600	98,500
Commercial Loans [Member]
Activity in allowance for credit losses by portfolio segment [Roll Forward]
Balance, beginning of period	28,557	50,045	28,941	50,942
Charge-offs	(447)	(389)	(1,035)	(631)
Recoveries	837	61	930	179
Provision	3,411	(5,526)	3,522	(6,299)
Balance, end of period	32,358	44,191	32,358	44,191
Consumer Loans [Member]
Activity in allowance for credit losses by portfolio segment [Roll Forward]
Balance, beginning of period	43,591	34,580	44,253	37,803
Charge-offs	(3,509)	(3,271)	(7,100)	(7,619)
Recoveries	2,117	2,288	3,769	4,363
Provision	2,741	1,284	4,018	334
Balance, end of period	44,940	34,881	44,940	34,881
Residential [Member]
Activity in allowance for credit losses by portfolio segment [Roll Forward]
Balance, beginning of period	17,852	20,375	18,806	21,255
Charge-offs	(90)	(349)	(402)	(419)
Recoveries	302	376	452	639
Provision	(1,762)	(974)	(2,554)	(2,047)
Balance, end of period	$ 16,302	$ 19,428	$ 16,302	$ 19,428