Loans - Credit Quality (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	$ 20,416	$ 25,188
Total loans held for investment	3,071,761	3,098,220	$ 3,047,618
Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	2,624,489	2,657,301
Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	207,133	115,258
Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	89,643	150,593
Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	75,869	73,074
Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	54,211	74,995
Grade 9
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile		1,811
Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	1,148,850	1,053,925
Owner occupied commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	408,398	394,210
Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	1,068,742	1,143,751
Construction, land & land development
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	193,856	249,704
Residential mortgage
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	235,089	245,191
Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	16,826	11,439
Originated
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	2,485,239	2,301,928	2,152,059
Originated | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	2,200,493	2,081,325
Originated | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	125,798	72,082
Originated | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	55,956	82,438
Originated | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	60,605	26,320
Originated | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	42,387	37,952
Originated | Grade 9
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile		1,811
Originated | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	1,066,715	904,331	823,047
Originated | Commercial & Industrial | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	932,888	818,352
Originated | Commercial & Industrial | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	50,276	11,427
Originated | Commercial & Industrial | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	2,613	24,133
Originated | Commercial & Industrial | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	43,449	14,088
Originated | Commercial & Industrial | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	37,489	34,520
Originated | Commercial & Industrial | Grade 9
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile		1,811
Originated | Owner occupied commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	312,162	264,876	249,827
Originated | Owner occupied commercial real estate | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	300,558	247,868
Originated | Owner occupied commercial real estate | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	2,678	13,169
Originated | Owner occupied commercial real estate | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	8,426	513
Originated | Owner occupied commercial real estate | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	500	3,326
Originated | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	806,327	816,029	761,788
Originated | Commercial real estate | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	698,303	716,744
Originated | Commercial real estate | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	53,421	35,812
Originated | Commercial real estate | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	44,917	55,230
Originated | Commercial real estate | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	9,484	6,184
Originated | Commercial real estate | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	202	2,059
Originated | Construction, land & land development
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	146,522	179,999	180,315
Originated | Construction, land & land development | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	126,318	171,287
Originated | Construction, land & land development | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	12,688	5,590
Originated | Construction, land & land development | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile		1,931
Originated | Construction, land & land development | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	4,379	1,191
Originated | Construction, land & land development | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	3,137
Originated | Residential mortgage
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	138,095	127,445	128,077
Originated | Residential mortgage | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	127,082	118,042
Originated | Residential mortgage | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	6,734	6,079
Originated | Residential mortgage | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile		573
Originated | Residential mortgage | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	2,772	1,497
Originated | Residential mortgage | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	1,507	1,254
Originated | Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	15,418	9,248	9,005
Originated | Consumer and other | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	15,344	9,032
Originated | Consumer and other | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	1	5
Originated | Consumer and other | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile		58
Originated | Consumer and other | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	21	34
Originated | Consumer and other | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	52	119
Acquired
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	20,416	25,188
Total loans held for investment	586,522	796,292	895,559
Acquired | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	423,996	575,976
Acquired | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	81,335	43,176
Acquired | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	33,687	68,155
Acquired | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	15,264	46,754
Acquired | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	11,824	37,043
Acquired | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	3,339	4,506
Total loans held for investment	82,135	149,594	181,367
Acquired | Commercial & Industrial | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	41,279	69,304
Acquired | Commercial & Industrial | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	6,755	2,982
Acquired | Commercial & Industrial | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	12,864	15,528
Acquired | Commercial & Industrial | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	9,191	33,850
Acquired | Commercial & Industrial | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	8,707	23,424
Acquired | Owner occupied commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	4,283	5,339
Total loans held for investment	96,236	129,334	137,205
Acquired | Owner occupied commercial real estate | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	74,781	94,450
Acquired | Owner occupied commercial real estate | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	10,005	2,533
Acquired | Owner occupied commercial real estate | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile		9,788
Acquired | Owner occupied commercial real estate | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	4,533	8,282
Acquired | Owner occupied commercial real estate | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	2,634	8,942
Acquired | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	10,323	10,807
Total loans held for investment	262,415	327,722	347,854
Acquired | Commercial real estate | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	195,202	248,583
Acquired | Commercial real estate | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	39,539	23,854
Acquired | Commercial real estate | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	17,224	39,833
Acquired | Commercial real estate | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile		2,643
Acquired | Commercial real estate | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	127	2,002
Acquired | Construction, land & land development
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	17	1,819
Total loans held for investment	47,334	69,705	98,008
Acquired | Construction, land & land development | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	18,870	49,849
Acquired | Construction, land & land development | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	24,004	12,859
Acquired | Construction, land & land development | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	2,955	2,577
Acquired | Construction, land & land development | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	1,381	1,623
Acquired | Construction, land & land development | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	107	978
Acquired | Residential mortgage
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	2,454	2,717
Total loans held for investment	96,994	117,746	128,763
Acquired | Residential mortgage | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	92,668	111,818
Acquired | Residential mortgage | Grade 5
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	1,032	948
Acquired | Residential mortgage | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	644	215
Acquired | Residential mortgage | Grade 7
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	159	356
Acquired | Residential mortgage | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	37	1,692
Acquired | Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	1,408	2,191	$ 2,362
Acquired | Consumer and other | Grade 1 To 4
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	1,196	1,972
Acquired | Consumer and other | Grade 6
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile		214
Acquired | Consumer and other | Grade 8
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	$ 212	$ 5