Portfolio Loans - Activity in the allowance for loan losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Activity in the allowance for loan losses
ACL beginning balance	$ 101,048	$ 53,748	$ 50,648
Provision for credit losses	(15,101)	38,797	10,406
Charged-off	(4,783)	(11,088)	(11,760)
Recoveries	2,545	2,758	4,454
ACL ending balance	87,887	101,048	53,748
Allowance for loan losses Ending balance attributed to:
Collectively evaluated for impairment	84,298	99,423
Individually evaluated for impairment	3,589	1,625
Total	87,887	101,048	53,748
Loans:
Collectively evaluated for impairment	7,173,618	6,793,931
Individually evaluated for impairment	15,380	20,246
Total	7,188,998	6,814,177
Day 1 PCD
Activity in the allowance for loan losses
ACL beginning balance	4,178
ACL ending balance		4,178
Allowance for loan losses Ending balance attributed to:
Total		4,178
Commercial Loans
Activity in the allowance for loan losses
ACL beginning balance	23,866	18,291	17,829
Provision for credit losses	(2,160)	10,832	4,893
Charged-off	(2,026)	(6,376)	(6,478)
Recoveries	629	404	2,047
ACL ending balance	23,855	23,866	18,291
Allowance for loan losses Ending balance attributed to:
Collectively evaluated for impairment	20,291	22,266
Individually evaluated for impairment	3,564	1,600
Total	23,855	23,866	18,291
Loans:
Collectively evaluated for impairment	1,936,898	2,006,204
Individually evaluated for impairment	6,988	8,372
Total	1,943,886	2,014,576
Commercial Loans | Day 1 PCD
Activity in the allowance for loan losses
ACL beginning balance	3,546
ACL ending balance		3,546
Allowance for loan losses Ending balance attributed to:
Total		3,546
Commercial Real Estate Loans
Activity in the allowance for loan losses
ACL beginning balance	46,230	21,190	21,137
Provision for credit losses	(7,651)	17,511	3,002
Charged-off	(925)	(1,972)	(3,257)
Recoveries	259	195	308
ACL ending balance	38,249	46,230	21,190
Allowance for loan losses Ending balance attributed to:
Collectively evaluated for impairment	38,249	46,230
Total	38,249	46,230	21,190
Loans:
Collectively evaluated for impairment	3,114,057	2,886,468
Individually evaluated for impairment	5,750	6,067
Total	3,119,807	2,892,535
Commercial Real Estate Loans | Day 1 PCD
Activity in the allowance for loan losses
ACL beginning balance	336
ACL ending balance		336
Allowance for loan losses Ending balance attributed to:
Total		336
Real Estate Construction
Activity in the allowance for loan losses
ACL beginning balance	8,193	3,204	2,723
Provision for credit losses	(3,180)	1,452	(70)
Charged-off	(209)	(18)
Recoveries	298	601	551
ACL ending balance	5,102	8,193	3,204
Allowance for loan losses Ending balance attributed to:
Collectively evaluated for impairment	5,102	8,193
Total	5,102	8,193	3,204
Loans:
Collectively evaluated for impairment	385,724	461,494
Individually evaluated for impairment	272	292
Total	385,996	461,786
Retail real estate
Activity in the allowance for loan losses
ACL beginning balance	21,992	10,495	8,471
Provision for credit losses	(4,456)	9,050	2,102
Charged-off	(1,145)	(2,057)	(1,162)
Recoveries	1,069	1,212	1,084
ACL ending balance	17,589	21,992	10,495
Allowance for loan losses Ending balance attributed to:
Collectively evaluated for impairment	17,564	21,967
Individually evaluated for impairment	25	25
Total	17,589	21,992	10,495
Loans:
Collectively evaluated for impairment	1,510,606	1,402,337
Individually evaluated for impairment	2,370	5,515
Total	1,512,976	1,407,852
Retail real estate | Day 1 PCD
Activity in the allowance for loan losses
ACL beginning balance	129
ACL ending balance		129
Allowance for loan losses Ending balance attributed to:
Total		129
Retail other
Activity in the allowance for loan losses
ACL beginning balance	767	568	488
Provision for credit losses	2,346	(48)	479
Charged-off	(478)	(665)	(863)
Recoveries	290	346	464
ACL ending balance	3,092	767	568
Allowance for loan losses Ending balance attributed to:
Collectively evaluated for impairment	3,092	767
Total	3,092	767	568
Loans:
Collectively evaluated for impairment	226,333	37,428
Total	226,333	37,428
Retail other | Day 1 PCD
Activity in the allowance for loan losses
ACL beginning balance	$ 167
ACL ending balance		167
Allowance for loan losses Ending balance attributed to:
Total		167
Cumulative Effect, Period of Adoption, Adjustment
Activity in the allowance for loan losses
ACL beginning balance		16,833
ACL ending balance			16,833
Allowance for loan losses Ending balance attributed to:
Total			16,833
Cumulative Effect, Period of Adoption, Adjustment | Commercial Loans
Activity in the allowance for loan losses
ACL beginning balance		715
ACL ending balance			715
Allowance for loan losses Ending balance attributed to:
Total			715
Cumulative Effect, Period of Adoption, Adjustment | Commercial Real Estate Loans
Activity in the allowance for loan losses
ACL beginning balance		9,306
ACL ending balance			9,306
Allowance for loan losses Ending balance attributed to:
Total			9,306
Cumulative Effect, Period of Adoption, Adjustment | Real Estate Construction
Activity in the allowance for loan losses
ACL beginning balance		2,954
ACL ending balance			2,954
Allowance for loan losses Ending balance attributed to:
Total			2,954
Cumulative Effect, Period of Adoption, Adjustment | Retail real estate
Activity in the allowance for loan losses
ACL beginning balance		3,292
ACL ending balance			3,292
Allowance for loan losses Ending balance attributed to:
Total			3,292
Cumulative Effect, Period of Adoption, Adjustment | Retail other
Activity in the allowance for loan losses
ACL beginning balance		$ 566
ACL ending balance			566
Allowance for loan losses Ending balance attributed to:
Total			$ 566