LHFI and ACL, LHFI - Additional Information (Details 1) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) Region	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Accrued interest receivable	$ 26,700	$ 33,000
Maximum concentration of loan as a percentage of total LHFI	10.00%
Key market regions | Region	5
Loans and Leases Receivable, Related Parties	$ 26,300	37,700
New loan advances to related party	170,300
Loan repayment by related party	181,300
Decrease in loans due to changes in executive officers and directors	426
LHFI classified as TDRs	21,600	25,800	$ 31,500
LHFI classified as TDRs from bankruptcies, payment concessions, credits with interest-only payments and credits renewed at a rate that was not commensurate with that of new debt with similar risk	18,200	17,700	20,800
Unused commitments on TDRs	1,000	4,500	7,000
Financing receivable, related allowance	1,500	2,400	3,200
Financing receivable, related charge-offs	$ 3,700	2,300	$ 1,600
Period of extension on interest part of loans modified related to COVID-19	90 days
Period of extension on full payment deferrals part of loans modified related to COVID-19	90 days
Balance of loans remaining under some type of concession related to COVID-19	$ 1,100	$ 34,200