Allowance for Credit Losses - Activity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Allowance for loan and lease losses:
Balance at beginning of period	$ 157,262	$ 208,454
Charge-offs	(4,858)	(7,668)
Recoveries	2,259	3,080
Increase (decrease) in Provision	(4,383)	(3,500)
Balance at end of period	150,280	200,366
Commercial and Industrial
Allowance for loan and lease losses:
Balance at beginning of period	20,080	24,711
Charge-offs	(706)	(963)
Recoveries	53	215
Increase (decrease) in Provision	(267)	3,359
Balance at end of period	19,160	27,322
Commercial real estate
Allowance for loan and lease losses:
Balance at beginning of period	42,951	58,123
Charge-offs		(66)
Recoveries	14	3
Increase (decrease) in Provision	2,273	(6,369)
Balance at end of period	45,238	51,691
Construction
Allowance for loan and lease losses:
Balance at beginning of period	9,773	10,039
Recoveries		166
Increase (decrease) in Provision	(865)	347
Balance at end of period	8,908	10,552
Lease financing
Allowance for loan and lease losses:
Balance at beginning of period	1,659	3,298
Increase (decrease) in Provision	(297)	(101)
Balance at end of period	1,362	3,197
Residential. Mortgage
Allowance for loan and lease losses:
Balance at beginning of period	34,364	40,461
Charge-offs		(98)
Recoveries	16	17
Increase (decrease) in Provision	(3,492)	(1,909)
Balance at end of period	30,888	38,471
Consumer
Allowance for loan and lease losses:
Balance at beginning of period	42,793	64,659
Charge-offs	(4,109)	(6,541)
Recoveries	2,148	2,655
Increase (decrease) in Provision	(1,192)	1,692
Balance at end of period	39,640	62,465
Home equity line
Allowance for loan and lease losses:
Balance at beginning of period	5,642	7,163
Charge-offs	(43)
Recoveries	28	24
Increase (decrease) in Provision	(543)	(519)
Balance at end of period	$ 5,084	$ 6,668