Allowance For Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Allowance for loan losses:
Beginning balance	$ 31,991	$ 47,420	$ 26,364	$ 32,947
Provision	2,300	28,200	9,955	55,200
Charge-offs	(850)	(39,825)	(3,818)	(53,281)
Recoveries	39	116	979	1,045
Ending balance	33,480	35,911	33,480	35,911
Loans evaluated for impairment:
Collectively evaluated for impairment					$ 2,978,883	$ 2,979,708	$ 2,914,666
Individually evaluated for impairment					72,462	93,324	98,830
Purchased credit impaired					20,416	25,188	34,122
Total loans held for investment					3,071,761	3,098,220	3,047,618
Allowance for loans losses evaluated:
Collectively evaluated for impairment					25,572	24,467	22,495
Individually evaluated for impairment					7,774	1,775	11,584
Purchased credit impaired					134	122	1,832
Total allowance for loan losses	31,991	47,420	26,364	32,947	33,480	26,364	35,911
Commercial & Industrial
Loans evaluated for impairment:
Total loans held for investment					1,148,850	1,053,925
Owner occupied commercial real estate
Loans evaluated for impairment:
Total loans held for investment					408,398	394,210
Commercial real estate
Loans evaluated for impairment:
Total loans held for investment					1,068,742	1,143,751
Construction, land & land development
Loans evaluated for impairment:
Total loans held for investment					193,856	249,704
Residential mortgage
Loans evaluated for impairment:
Total loans held for investment					235,089	245,191
Consumer and other
Loans evaluated for impairment:
Total loans held for investment					16,826	11,439
Originated
Allowance for loan losses:
Beginning balance	30,529	44,201	23,855	32,722
Provision	2,479	22,844	9,986	46,534
Charge-offs	(845)	(36,410)	(2,422)	(49,323)
Recoveries	18	41	762	743
Ending balance	32,181	30,676	32,181	30,676
Loans evaluated for impairment:
Collectively evaluated for impairment					2,438,715	2,256,897	2,085,991
Individually evaluated for impairment					46,524	45,031	66,068
Total loans held for investment					2,485,239	2,301,928	2,152,059
Allowance for loans losses evaluated:
Collectively evaluated for impairment					24,429	23,342	21,778
Individually evaluated for impairment					7,752	513	8,898
Total allowance for loan losses	30,529	44,201	23,855	32,722	32,181	23,855	30,676
Originated | Commercial & Industrial
Allowance for loan losses:
Beginning balance	16,606	30,880	9,491	23,084
Provision	2,031	22,308	10,002	42,286
Charge-offs	(836)	(36,330)	(2,280)	(49,201)
Recoveries	5	13	593	702
Ending balance	17,806	16,871	17,806	16,871
Loans evaluated for impairment:
Collectively evaluated for impairment					1,025,109	867,924	766,494
Individually evaluated for impairment					41,606	36,407	56,553
Total loans held for investment					1,066,715	904,331	823,047
Allowance for loans losses evaluated:
Collectively evaluated for impairment					10,391	9,097	8,106
Individually evaluated for impairment					7,415	394	8,765
Total allowance for loan losses	16,606	30,880	9,491	23,084	17,806	9,491	16,871
Originated | Owner occupied commercial real estate
Allowance for loan losses:
Beginning balance	2,825	2,124	2,609	1,675
Provision	85	278	301	727
Ending balance	2,910	2,402	2,910	2,402
Loans evaluated for impairment:
Collectively evaluated for impairment					312,162	264,876	248,373
Individually evaluated for impairment							1,454
Total loans held for investment					312,162	264,876	249,827
Allowance for loans losses evaluated:
Collectively evaluated for impairment					2,910	2,609	2,402
Total allowance for loan losses	2,825	2,124	2,609	1,675	2,910	2,609	2,402
Originated | Commercial real estate
Allowance for loan losses:
Beginning balance	8,185	7,540	8,576	4,525
Provision	131	669	(260)	3,684
Charge-offs		(26)		(26)
Ending balance	8,316	8,183	8,316	8,183
Loans evaluated for impairment:
Collectively evaluated for impairment					806,125	808,874	754,527
Individually evaluated for impairment					202	7,155	7,261
Total loans held for investment					806,327	816,029	761,788
Allowance for loans losses evaluated:
Collectively evaluated for impairment					8,316	8,576	8,183
Total allowance for loan losses	8,185	7,540	8,576	4,525	8,316	8,576	8,183
Originated | Construction, land & land development
Allowance for loan losses:
Beginning balance	1,576	2,426	1,852	2,337
Provision	255	(588)	(21)	(499)
Ending balance	1,831	1,838	1,831	1,838
Loans evaluated for impairment:
Collectively evaluated for impairment					143,385	179,999	180,315
Individually evaluated for impairment					3,137
Total loans held for investment					146,522	179,999	180,315
Allowance for loans losses evaluated:
Collectively evaluated for impairment					1,523	1,852	1,838
Individually evaluated for impairment					308
Total allowance for loan losses	1,576	2,426	1,852	2,337	1,831	1,852	1,838
Originated | Residential mortgage
Allowance for loan losses:
Beginning balance	1,165	1,172	1,134	815
Provision	(6)	(4)	(9)	350
Recoveries	13	23	47	26
Ending balance	1,172	1,191	1,172	1,191
Loans evaluated for impairment:
Collectively evaluated for impairment					136,588	126,190	127,498
Individually evaluated for impairment					1,507	1,255	579
Total loans held for investment					138,095	127,445	128,077
Allowance for loans losses evaluated:
Collectively evaluated for impairment					1,172	1,134	1,177
Individually evaluated for impairment							14
Total allowance for loan losses	1,165	1,172	1,134	815	1,172	1,134	1,191
Originated | Consumer and other
Allowance for loan losses:
Beginning balance	172	59	193	286
Provision	(17)	181	(27)	(14)
Charge-offs	(9)	(54)	(142)	(96)
Recoveries		5	122	15
Ending balance	146	191	146	191
Loans evaluated for impairment:
Collectively evaluated for impairment					15,346	9,034	8,784
Individually evaluated for impairment					72	214	221
Total loans held for investment					15,418	9,248	9,005
Allowance for loans losses evaluated:
Collectively evaluated for impairment					117	74	72
Individually evaluated for impairment					29	119	119
Total allowance for loan losses	172	59	193	286	146	193	191
Acquired
Allowance for loan losses:
Beginning balance	1,462	3,219	2,509	225
Provision	(179)	5,356	(31)	8,666
Charge-offs	(5)	(3,415)	(1,396)	(3,958)
Recoveries	21	75	217	302
Ending balance	1,299	5,235	1,299	5,235
Loans evaluated for impairment:
Collectively evaluated for impairment					540,168	722,811	828,675
Individually evaluated for impairment					25,938	48,293	32,762
Purchased credit impaired					20,416	25,188	34,122
Total loans held for investment					586,522	796,292	895,559
Allowance for loans losses evaluated:
Collectively evaluated for impairment					1,143	1,125	717
Individually evaluated for impairment					22	1,262	2,686
Purchased credit impaired					134	122	1,832
Total allowance for loan losses	1,462	3,219	2,509	225	1,299	2,509	5,235
Acquired | Commercial & Industrial
Allowance for loan losses:
Beginning balance	157	410	1,260	46
Provision	(145)	3,719	(984)	4,360
Charge-offs	(4)	(1,459)	(338)	(1,804)
Recoveries	7	24	77	92
Ending balance	15	2,694	15	2,694
Loans evaluated for impairment:
Collectively evaluated for impairment					61,035	110,413	150,937
Individually evaluated for impairment					17,761	34,675	25,652
Purchased credit impaired					3,339	4,506	4,778
Total loans held for investment					82,135	149,594	181,367
Allowance for loans losses evaluated:
Collectively evaluated for impairment					15
Individually evaluated for impairment						1,260	2,684
Purchased credit impaired							10
Total allowance for loan losses	157	410	1,260	46	15	1,260	2,694
Acquired | Owner occupied commercial real estate
Allowance for loan losses:
Beginning balance		580		4
Provision		383	957	1,137
Charge-offs		(977)	(961)	(1,155)
Recoveries		17	4	17
Ending balance		3		3
Loans evaluated for impairment:
Collectively evaluated for impairment					85,073	115,053	128,633
Individually evaluated for impairment					6,880	8,942	2,583
Purchased credit impaired					4,283	5,339	5,989
Total loans held for investment					96,236	129,334	137,205
Allowance for loans losses evaluated:
Purchased credit impaired							3
Total allowance for loan losses		580		4			3
Acquired | Commercial real estate
Allowance for loan losses:
Beginning balance	487	25	437	166
Provision	167	466	214	325
Charge-offs		(466)		(466)
Recoveries	4		7
Ending balance	658	25	658	25
Loans evaluated for impairment:
Collectively evaluated for impairment					251,965	314,913	333,271
Individually evaluated for impairment					127	2,002	2,623
Purchased credit impaired					10,323	10,807	11,960
Total loans held for investment					262,415	327,722	347,854
Allowance for loans losses evaluated:
Collectively evaluated for impairment					569	429
Purchased credit impaired					89	8	25
Total allowance for loan losses	487	25	437	166	658	437	25
Acquired | Construction, land & land development
Allowance for loan losses:
Beginning balance	3	825	115	8
Provision	19	671	(72)	1,415
Charge-offs			(95)
Recoveries	1	6	75	79
Ending balance	23	1,502	23	1,502
Loans evaluated for impairment:
Collectively evaluated for impairment					46,396	66,908	89,319
Individually evaluated for impairment					921	978	358
Purchased credit impaired					17	1,819	8,331
Total loans held for investment					47,334	69,705	98,008
Allowance for loans losses evaluated:
Collectively evaluated for impairment					23	14	3
Purchased credit impaired						101	1,499
Total allowance for loan losses	3	825	115	8	23	115	1,502
Acquired | Residential mortgage
Allowance for loan losses:
Beginning balance	598	1,368	685	1
Provision	(10)	122	(136)	1,421
Charge-offs		(512)		(518)
Recoveries	8	22	47	96
Ending balance	596	1,000	596	1,000
Loans evaluated for impairment:
Collectively evaluated for impairment					94,503	113,338	124,165
Individually evaluated for impairment					37	1,691	1,534
Purchased credit impaired					2,454	2,717	3,064
Total loans held for investment					96,994	117,746	128,763
Allowance for loans losses evaluated:
Collectively evaluated for impairment					532	672	705
Individually evaluated for impairment					19
Purchased credit impaired					45	13	295
Total allowance for loan losses	598	1,368	685	1	596	685	1,000
Acquired | Consumer and other
Allowance for loan losses:
Beginning balance	217	11	12
Provision	(210)	(5)	(10)	8
Charge-offs	(1)	(1)	(2)	(15)
Recoveries	1	6	7	18
Ending balance	7	11	7	11
Loans evaluated for impairment:
Collectively evaluated for impairment					1,196	2,186	2,350
Individually evaluated for impairment					212	5	12
Total loans held for investment					1,408	2,191	2,362
Allowance for loans losses evaluated:
Collectively evaluated for impairment					4	10	9
Individually evaluated for impairment					3	2	2
Total allowance for loan losses	$ 217	$ 11	$ 12	$ 11	$ 7	$ 12	$ 11