Loans and Allowance for Credit Losses - Allowance for loan losses by loan product and impairment methodology (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Allowance for loan losses
General	$ 28,113	$ 29,539
Specific	17,264	17,193
Ending Balance	45,377	46,732	$ 7,441
Originated SBC loans
Allowance for loan losses
General	2,666	2,640
Specific	4,194	6,200
Ending Balance	6,860	8,840	304
Originated Transitional loans
Allowance for loan losses
General	15,841	14,995
Specific	4,375
Ending Balance	20,216	14,995	188
Acquired loans
Allowance for loan losses
General	2,953	5,457
Specific	3,168	2,840
Ending Balance	6,121	8,297	3,054
Acquired SBA 7(a) loans
Allowance for loan losses
General	543	767
Specific	2,541	3,782
Ending Balance	3,084	4,549	2,114
Originated SBA 7(a) loans
Allowance for loan losses
General	6,110	5,680
Specific	2,986	4,371
Ending Balance	$ 9,096	$ 10,051	$ 1,781