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, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period			$ 196,955
Provision for credit loss expense	$ 20,222	$ (15,897)	36,199	$ (5,405)
Balance, end of period	218,547		218,547
Loans, Excluding Acquired Loans
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	209,966	212,611	196,955	205,332
Acquisition adjustment for PCD loans		1,057		5,100
Provision for credit loss expense	20,222	(15,897)	36,199	(5,405)
Charge-offs	(12,893)	(3,412)	(19,777)	(13,875)
Recoveries	1,252	3,230	5,170	6,437
Net (charge-offs) recoveries	(11,641)	(182)	(14,607)	(7,438)
Balance, end of period	218,547	197,589	218,547	197,589
Loans, Excluding Acquired Loans | Other Consumer and Other
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	6,838	6,704	6,614	4,617
Acquisition adjustment for PCD loans		0		2
Provision for credit loss expense	(1,105)	840	(435)	3,168
Charge-offs	(633)	(506)	(1,755)	(1,438)
Recoveries	344	278	1,020	967
Net (charge-offs) recoveries	(289)	(228)	(735)	(471)
Balance, end of period	5,444	7,316	5,444	7,316
Loans, Excluding Acquired Loans | Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	30,985	32,817	34,406	17,458
Acquisition adjustment for PCD loans		1,057		1,911
Provision for credit loss expense	4,095	(613)	774	19,721
Charge-offs	(1,219)	(1,873)	(2,857)	(8,880)
Recoveries	245	720	1,783	1,898
Net (charge-offs) recoveries	(974)	(1,153)	(1,074)	(6,982)
Balance, end of period	34,106	32,108	34,106	32,108
Loans, Excluding Acquired Loans | Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	165,813	166,481	150,795	179,270
Acquisition adjustment for PCD loans		0		3,187
Provision for credit loss expense	16,528	(17,243)	32,013	(33,436)
Charge-offs	(9,723)	(130)	(11,362)	(730)
Recoveries	429	1,982	1,601	2,799
Net (charge-offs) recoveries	(9,294)	1,852	(9,761)	2,069
Balance, end of period	173,047	151,090	173,047	151,090
Loans, Excluding Acquired Loans | Consumer | Credit cards
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	6,330	6,609	5,140	3,987
Acquisition adjustment for PCD loans		0		0
Provision for credit loss expense	704	1,119	3,847	5,142
Charge-offs	(1,318)	(903)	(3,803)	(2,827)
Recoveries	234	250	766	773
Net (charge-offs) recoveries	(1,084)	(653)	(3,037)	(2,054)
Balance, end of period	$ 5,950	$ 7,075	$ 5,950	$ 7,075