Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Additional Information (Details 1) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($) Region	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Accrued interest receivable	$ 27,700		$ 26,700
Maximum concentration of loan as a percentage of total LHFI	10.00%
Key market regions | Region	5
LHFI classified as TDRs	$ 23,300	$ 22,900
LHFI classified as TDRs from credits with interest only payments and credits renewed at a rate that was not commensurate with that of new debt with similar risk	21,700	17,300
Unused commitments on TDRs	0	0
Financing receivable, related allowance	1,900	7,500
Financing receivable, related charge-offs	$ 0	$ 0