Loans and Allowance for Credit Losses - Schedule of Activity in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	$ 107,341	$ 131,388
Allowance Established for Acquired PCD Loans	78,531	0
Charge-offs	(4,664)	(1,570)
Recoveries	1,890	1,575
Provision for Credit Losses	97,409	(17,356)
Balance at End of Period	280,507	114,037
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	27,232	30,567
Allowance Established for Acquired PCD Loans	35,040	0
Charge-offs	(1,880)	(407)
Recoveries	325	238
Provision for Credit Losses	38,754	(5,268)
Balance at End of Period	99,471	25,130
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	64,004	75,810
Allowance Established for Acquired PCD Loans	42,601	0
Charge-offs	(507)	(1)
Recoveries	182	73
Provision for Credit Losses	34,210	(5,321)
Balance at End of Period	140,490	70,561
BBCC
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	2,458	6,120
Allowance Established for Acquired PCD Loans	0	0
Charge-offs	(28)	(36)
Recoveries	57	41
Provision for Credit Losses	(418)	(3,588)
Balance at End of Period	2,069	2,537
Residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	9,347	12,608
Allowance Established for Acquired PCD Loans	136	0
Charge-offs	(185)	(158)
Recoveries	440	87
Provision for Credit Losses	7,514	(2,272)
Balance at End of Period	17,252	10,265
Indirect
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	1,743	3,580
Allowance Established for Acquired PCD Loans	0	0
Charge-offs	(483)	(584)
Recoveries	222	537
Provision for Credit Losses	166	(1,278)
Balance at End of Period	1,648	2,255
Direct
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	528	855
Allowance Established for Acquired PCD Loans	31	0
Charge-offs	(1,530)	(302)
Recoveries	582	260
Provision for Credit Losses	14,839	(148)
Balance at End of Period	14,450	665
Home equity
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	2,029	1,848
Allowance Established for Acquired PCD Loans	723	0
Charge-offs	(51)	(82)
Recoveries	82	339
Provision for Credit Losses	2,344	519
Balance at End of Period	$ 5,127	$ 2,624