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Loans -Loans Balance (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Loans held-for-investment:
Total loan balance	$ 2,534,163	$ 1,886,732
Deferred loan fees, net	(319)	(327)
Loans, net of deferred fees	2,533,844	1,886,405	$ 1,582,667
Allowance for loan losses	(23,285)	(27,848)	(19,658)	$ (19,089)
Loans, net	2,510,559	1,858,557
Commercial
Loans held-for-investment:
Total loan balance		597,763
Commercial
Loans held-for-investment:
Total loan balance	631,547	597,763
Allowance for loan losses	(10,453)	(17,061)	(10,608)	(10,656)
Real estate
Loans held-for-investment:
Total loan balance	1,882,734	1,276,516
Allowance for loan losses	(12,750)	(10,671)	(8,950)	(8,327)
Real estate \| CRE
Loans held-for-investment:
Total loan balance	1,510,592	994,067
Real estate \| Land and construction
Loans held-for-investment:
Total loan balance	150,634	122,358
Real estate \| Home equity
Loans held-for-investment:
Total loan balance	175,252	109,112
Real estate \| Residential mortgages
Loans held-for-investment:
Total loan balance	46,256	50,979
Consumer
Loans held-for-investment:
Total loan balance	19,882	12,453
Allowance for loan losses	$ (82)	$ (116)	$ (100)	$ (106)