Allowance for Credit Losses - Activity (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Allowance for loan and lease losses:
Balance at beginning of period	$ 150,280	$ 200,366	$ 157,262	$ 208,454
Charge-offs	(5,022)	(4,247)	(9,880)	(11,915)
Recoveries	2,684	3,148	4,943	6,228
Provision	1,000	(30,119)	(3,383)	(33,619)
Balance at end of period	148,942	169,148	148,942	169,148
Commercial and Industrial
Allowance for loan and lease losses:
Balance at beginning of period	19,160	27,322	20,080	24,711
Charge-offs	(243)	(330)	(949)	(1,293)
Recoveries	301	287	354	502
Provision	(3,294)	(4,216)	(3,561)	(857)
Balance at end of period	15,924	23,063	15,924	23,063
Commercial real estate
Allowance for loan and lease losses:
Balance at beginning of period	45,238	51,691	42,951	58,123
Charge-offs				(66)
Recoveries		12	14	15
Provision	(512)	(4,670)	1,761	(11,039)
Balance at end of period	44,726	47,033	44,726	47,033
Construction
Allowance for loan and lease losses:
Balance at beginning of period	8,908	10,552	9,773	10,039
Recoveries				166
Provision	(3,541)	(400)	(4,406)	(53)
Balance at end of period	5,367	10,152	5,367	10,152
Lease financing
Allowance for loan and lease losses:
Balance at beginning of period	1,362	3,197	1,659	3,298
Recoveries	60		60
Provision	(24)	(130)	(321)	(231)
Balance at end of period	1,398	3,067	1,398	3,067
Residential. Mortgage
Allowance for loan and lease losses:
Balance at beginning of period			34,364	40,461
Charge-offs				(98)
Recoveries			208	31
Provision			(937)	(6,186)
Balance at end of period	33,635	34,208	33,635	34,208
Consumer
Allowance for loan and lease losses:
Balance at beginning of period		62,465	42,793	64,659
Charge-offs		(3,917)	(7,768)	(10,458)
Recoveries		2,797	4,088	5,452
Provision		(15,970)	4,045	(14,278)
Balance at end of period	43,158	45,375	43,158	45,375
Residential mortgage | Residential. Mortgage
Allowance for loan and lease losses:
Balance at beginning of period	30,888	38,471
Recoveries	192	14
Provision	2,555	(4,277)
Balance at end of period	33,635	34,208	33,635	34,208
Home equity line
Allowance for loan and lease losses:
Balance at beginning of period	5,084	6,668	5,642	7,163
Charge-offs	(1,120)		(1,163)
Recoveries	191	38	219	62
Provision	579	(456)	36	(975)
Balance at end of period	4,734	$ 6,250	4,734	$ 6,250
Consumer Member | Consumer
Allowance for loan and lease losses:
Balance at beginning of period	39,640
Charge-offs	(3,659)
Recoveries	1,940
Provision	5,237
Balance at end of period	$ 43,158		$ 43,158