Loans - Past Due (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	$ 6,046	$ 1,987
Non- Accrual Loans	1,446	1,090
Current	1,798,401	1,355,489
Total Loans	1,804,447	1,357,476	[1]
Commercial
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	1,046	103
Non- Accrual Loans	110	83
Current	323,462	285,869
Total Loans	324,508	285,972
Commercial real estate
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Loans	1,027,007	753,040
Commercial real estate | Construction and land development
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	21	27
Non- Accrual Loans	21	27
Current	143,767	97,213
Total Loans	143,788	97,240
Commercial real estate | Real estate
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	1,783	239
Non- Accrual Loans	299	197
Current	881,436	655,561
Total Loans	883,219	655,800
Residential
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Loans	440,907	313,371
Residential | Real estate
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	2,474	1,344
Non- Accrual Loans	845	659
Current	316,359	208,094
Total Loans	318,833	209,438
Residential | Home equity
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	638	250
Non- Accrual Loans	171	124
Current	121,436	103,683
Total Loans	122,074	103,933
Consumer
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	84	24
Non- Accrual Loans	0	0
Current	11,941	5,069
Total Loans	12,025	5,093
30- 59 Days Past Due
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	3,008	665
30- 59 Days Past Due | Commercial
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	776	20
30- 59 Days Past Due | Commercial real estate | Construction and land development
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	0	0
30- 59 Days Past Due | Commercial real estate | Real estate
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	865	42
30- 59 Days Past Due | Residential | Real estate
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	976	456
30- 59 Days Past Due | Residential | Home equity
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	321	126
30- 59 Days Past Due | Consumer
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	70	21
60-89 Days Past Due
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	718	160
60-89 Days Past Due | Commercial
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	121	0
60-89 Days Past Due | Commercial real estate | Construction and land development
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	0	0
60-89 Days Past Due | Commercial real estate | Real estate
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	483	0
60-89 Days Past Due | Residential | Real estate
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	5	157
60-89 Days Past Due | Residential | Home equity
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	95	0
60-89 Days Past Due | Consumer
Analysis by portfolio segment of the entity's past due loans [Abstract]
Total Past Due	14	3
90 Days Past Due and Still Accruing
Analysis by portfolio segment of the entity's past due loans [Abstract]
90 Days Past Due and Still Accruing	874	72
90 Days Past Due and Still Accruing | Commercial
Analysis by portfolio segment of the entity's past due loans [Abstract]
90 Days Past Due and Still Accruing	39	0
90 Days Past Due and Still Accruing | Commercial real estate | Construction and land development
Analysis by portfolio segment of the entity's past due loans [Abstract]
90 Days Past Due and Still Accruing	0	0
90 Days Past Due and Still Accruing | Commercial real estate | Real estate
Analysis by portfolio segment of the entity's past due loans [Abstract]
90 Days Past Due and Still Accruing	136	0
90 Days Past Due and Still Accruing | Residential | Real estate
Analysis by portfolio segment of the entity's past due loans [Abstract]
90 Days Past Due and Still Accruing	648	72
90 Days Past Due and Still Accruing | Residential | Home equity
Analysis by portfolio segment of the entity's past due loans [Abstract]
90 Days Past Due and Still Accruing	51	0
90 Days Past Due and Still Accruing | Consumer
Analysis by portfolio segment of the entity's past due loans [Abstract]
90 Days Past Due and Still Accruing	$ 0	$ 0

[1] Derived from audited consolidated financial statements.