Loans and Allowance for Credit Losses - Activity in the Allowance for Loan Losses, by Portfolio Segment, for the Current Year (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period			$ 205,332
Provision for credit loss expense	$ (15,897)	$ (19,890)	(5,405)	$ (29,901)
Balance, end of period	197,589		197,589
Loans, Excluding Acquired Loans
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	212,611	227,239	205,332	238,050
Acquisition adjustment for PCD loans	1,057		5,100
Provision for credit loss expense	(15,897)	(19,890)	(5,405)	(29,901)
Charge-offs	(3,412)	(8,047)	(13,875)	(14,503)
Recoveries	3,230	3,206	6,437	8,862
Net (charge-offs) recoveries	(182)	(4,841)	(7,438)	(5,641)
Balance, end of period	197,589	202,508	197,589	202,508
Loans, Excluding Acquired Loans | Other Consumer and Other
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	6,704	3,616	4,617	5,617
Provision for credit loss expense	840	(122)	3,168	(1,737)
Charge-offs	(506)	(463)	(1,438)	(1,577)
Recoveries	278	408	967	1,136
Net (charge-offs) recoveries	(228)	(55)	(471)	(441)
Balance, end of period	7,316	3,439	7,316	3,439
Loans, Excluding Acquired Loans | Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	32,817	29,793	17,458	42,093
Acquisition adjustment for PCD loans	1,057		1,911
Provision for credit loss expense	(613)	(11,853)	19,721	(25,453)
Charge-offs	(1,873)	(932)	(8,880)	(2,099)
Recoveries	720	463	1,898	2,930
Net (charge-offs) recoveries	(1,153)	(469)	(6,982)	831
Balance, end of period	32,108	17,471	32,108	17,471
Loans, Excluding Acquired Loans | Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	166,481	188,388	179,270	182,868
Acquisition adjustment for PCD loans	0		3,187
Provision for credit loss expense	(17,243)	(7,668)	(33,436)	(1,948)
Charge-offs	(130)	(5,941)	(730)	(8,068)
Recoveries	1,982	2,068	2,799	3,995
Net (charge-offs) recoveries	1,852	(3,873)	2,069	(4,073)
Balance, end of period	151,090	176,847	151,090	176,847
Loans, Excluding Acquired Loans | Consumer | Credit cards
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	6,609	5,442	3,987	7,472
Acquisition adjustment for PCD loans	0		0
Provision for credit loss expense	1,119	(247)	5,142	(763)
Charge-offs	(903)	(711)	(2,827)	(2,759)
Recoveries	250	267	773	801
Net (charge-offs) recoveries	(653)	(444)	(2,054)	(1,958)
Balance, end of period	7,075	$ 4,751	7,075	$ 4,751
Loans, Excluding Acquired Loans | Consumer | Other Consumer and Other
Allowance for Loan and Lease Losses [Roll Forward]
Acquisition adjustment for PCD loans	$ 0		$ 2