Loans - Risk category of loans by loan segment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	$ 1,912,038	$ 1,664,931
Pass
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	1,904,068	1,651,089
Watch
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	5,275	9,658
Substandard
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	2,695	4,184
Commercial
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	276,035	260,833
Commercial | Pass
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	275,741	260,225
Commercial | Watch
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	21	600
Commercial | Substandard
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	273	8
Construction and Land Development
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	196,776	210,041
Construction and Land Development | Pass
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	196,462	207,174
Construction and Land Development | Watch
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	138	2,669
Construction and Land Development | Substandard
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	176	198
HELOC and 1-4 Family Junior Mortgage
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	28,621	31,256
HELOC and 1-4 Family Junior Mortgage | Pass
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	28,483	30,669
HELOC and 1-4 Family Junior Mortgage | Watch
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	138	587
1st REM - 1-4 Family
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	36,671	37,905
1st REM - 1-4 Family | Pass
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	36,370	37,526
1st REM - 1-4 Family | Watch
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	124	126
1st REM - 1-4 Family | Substandard
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	177	253
LOCs and 2nd REM - Rentals
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	18,671	12,443
LOCs and 2nd REM - Rentals | Pass
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	17,890	11,341
LOCs and 2nd REM - Rentals | Watch
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	479	628
LOCs and 2nd REM - Rentals | Substandard
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	302	474
1st REM - Rentals
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	176,648	145,169
1st REM - Rentals | Pass
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	174,781	142,357
1st REM - Rentals | Watch
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	1,287	1,854
1st REM - Rentals | Substandard
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	580	958
Multifamily
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	515,014	407,934
Multifamily | Pass
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	515,014	407,934
CRE Owner Occupied
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	66,584	64,458
CRE Owner Occupied | Pass
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	65,411	62,223
CRE Owner Occupied | Substandard
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	1,173	2,235
CRE Non-owner Occupied
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	592,545	490,632
CRE Non-owner Occupied | Pass
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	589,457	487,438
CRE Non-owner Occupied | Watch
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	3,088	3,194
Consumer and other
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	4,473	4,260
Consumer and other | Pass
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	4,459	4,202
Consumer and other | Substandard
Risk category of loans by loan segment, based on the most recent analysis performed by management
Totals	$ 14	$ 58