Allowance For Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Allowance for loan losses:
Beginning balance	$ 26,364	$ 32,947	$ 32,947
Provision	6,145	16,000	64,700
Charge-offs	(1,415)	(9,906)	(72,585)
Recoveries	842	673	1,302
Ending balance	31,936	39,714	26,364
Loans evaluated for impairment:
Collectively evaluated for impairment				$ 2,909,117	$ 2,979,708	$ 3,069,380
Individually evaluated for impairment				80,682	93,324	56,151
Purchased credit impaired				22,476	25,188	42,652
Total loans held for investment				3,012,275	3,098,220	3,168,183
Allowance for loans losses evaluated:
Collectively evaluated for impairment				23,827	24,467	26,227
Individually evaluated for impairment				8,092	1,775	13,435
Purchased credit impaired				17	122	52
Total allowance for loan losses	26,364	32,947	32,947	31,936	26,364	39,714
Commercial & Industrial
Loans evaluated for impairment:
Total loans held for investment				1,012,982	1,053,925
Owner occupied commercial real estate
Loans evaluated for impairment:
Total loans held for investment				415,595	394,210
Commercial real estate
Loans evaluated for impairment:
Total loans held for investment				1,129,031	1,143,751
Construction, land & land development
Loans evaluated for impairment:
Total loans held for investment				201,946	249,704
Residential mortgage
Loans evaluated for impairment:
Total loans held for investment				241,839	245,191
Consumer and other
Loans evaluated for impairment:
Total loans held for investment				10,882	11,439
Originated
Allowance for loan losses:
Beginning balance	23,855	32,722	32,722
Provision	5,691	14,665	55,981
Charge-offs	(1,143)	(9,885)	(65,820)
Recoveries	708	581	972
Ending balance	29,111	38,083	23,855
Loans evaluated for impairment:
Collectively evaluated for impairment				2,237,049	2,256,897	2,023,179
Individually evaluated for impairment				45,162	45,031	52,369
Total loans held for investment				2,282,211	2,301,928	2,075,548
Allowance for loans losses evaluated:
Collectively evaluated for impairment				22,877	23,342	25,210
Individually evaluated for impairment				6,234	513	12,873
Total allowance for loan losses	23,855	32,722	32,722	29,111	23,855	38,083
Originated | Commercial & Industrial
Allowance for loan losses:
Beginning balance	9,491	23,084	23,084
Provision	6,234	10,557	51,189
Charge-offs	(1,135)	(9,865)	(65,684)
Recoveries	565	576	902
Ending balance	15,155	24,352	9,491
Loans evaluated for impairment:
Collectively evaluated for impairment				849,529	867,924	803,031
Individually evaluated for impairment				40,319	36,407	44,507
Total loans held for investment				889,848	904,331	847,538
Allowance for loans losses evaluated:
Collectively evaluated for impairment				9,041	9,097	11,579
Individually evaluated for impairment				6,114	394	12,773
Total allowance for loan losses	9,491	23,084	23,084	15,155	9,491	24,352
Originated | Owner occupied commercial real estate
Allowance for loan losses:
Beginning balance	2,609	1,675	1,675
Provision	154	408	934
Ending balance	2,763	2,083	2,609
Loans evaluated for impairment:
Collectively evaluated for impairment				292,413	264,876	204,260
Individually evaluated for impairment						790
Total loans held for investment				292,413	264,876	205,050
Allowance for loans losses evaluated:
Collectively evaluated for impairment				2,763	2,609	2,083
Total allowance for loan losses	2,609	1,675	1,675	2,763	2,609	2,083
Originated | Commercial real estate
Allowance for loan losses:
Beginning balance	8,576	4,525	4,525
Provision	(229)	2,675	4,077
Charge-offs			(26)
Ending balance	8,347	7,200	8,576
Loans evaluated for impairment:
Collectively evaluated for impairment				807,005	808,874	631,246
Individually evaluated for impairment				2,021	7,155	5,293
Total loans held for investment				809,026	816,029	636,539
Allowance for loans losses evaluated:
Collectively evaluated for impairment				8,347	8,576	7,200
Total allowance for loan losses	8,576	4,525	4,525	8,347	8,576	7,200
Originated | Construction, land & land development
Allowance for loan losses:
Beginning balance	1,852	2,337	2,337
Provision	(316)	499	(485)
Recoveries		1
Ending balance	1,536	2,837	1,852
Loans evaluated for impairment:
Collectively evaluated for impairment				151,114	179,999	252,184
Individually evaluated for impairment						458
Total loans held for investment				151,114	179,999	252,642
Allowance for loans losses evaluated:
Collectively evaluated for impairment				1,536	1,852	2,751
Individually evaluated for impairment						86
Total allowance for loan losses	1,852	2,337	2,337	1,536	1,852	2,837
Originated | Residential mortgage
Allowance for loan losses:
Beginning balance	1,134	815	815
Provision	(40)	429	271
Recoveries	25		48
Ending balance	1,119	1,244	1,134
Loans evaluated for impairment:
Collectively evaluated for impairment				128,185	126,190	122,788
Individually evaluated for impairment				2,614	1,255	1,153
Total loans held for investment				130,799	127,445	123,941
Allowance for loans losses evaluated:
Collectively evaluated for impairment				1,119	1,134	1,230
Individually evaluated for impairment						14
Total allowance for loan losses	1,134	815	815	1,119	1,134	1,244
Originated | Consumer and other
Allowance for loan losses:
Beginning balance	193	286	286
Provision	(112)	97	(5)
Charge-offs	(8)	(20)	(110)
Recoveries	118	4	22
Ending balance	191	367	193
Loans evaluated for impairment:
Collectively evaluated for impairment				8,803	9,034	9,670
Individually evaluated for impairment				208	214	168
Total loans held for investment				9,011	9,248	9,838
Allowance for loans losses evaluated:
Collectively evaluated for impairment				71	74	367
Individually evaluated for impairment				120	119
Total allowance for loan losses	193	286	286	191	193	367
Acquired
Allowance for loan losses:
Beginning balance	2,509	225	225
Provision	454	1,335	8,719
Charge-offs	(272)	(21)	(6,765)
Recoveries	134	92	330
Ending balance	2,825	1,631	2,509
Loans evaluated for impairment:
Collectively evaluated for impairment				672,068	722,811	1,046,201
Individually evaluated for impairment				35,520	48,293	3,782
Purchased credit impaired				22,476	25,188	42,652
Total loans held for investment				730,064	796,292	1,092,635
Allowance for loans losses evaluated:
Collectively evaluated for impairment				950	1,125	1,017
Individually evaluated for impairment				1,858	1,262	562
Purchased credit impaired				17	122	52
Total allowance for loan losses	2,509	225	225	2,825	2,509	1,631
Acquired | Commercial & Industrial
Allowance for loan losses:
Beginning balance	1,260	46	46
Provision	(517)	342	3,816
Charge-offs	(177)	(15)	(2,700)
Recoveries	20	6	98
Ending balance	586	379	1,260
Loans evaluated for impairment:
Collectively evaluated for impairment				97,312	110,413	271,962
Individually evaluated for impairment				22,017	34,675	419
Purchased credit impaired				3,805	4,506	10,791
Total loans held for investment				123,134	149,594	283,172
Allowance for loans losses evaluated:
Collectively evaluated for impairment						1
Individually evaluated for impairment				586	1,260	368
Purchased credit impaired						10
Total allowance for loan losses	1,260	46	46	586	1,260	379
Acquired | Owner occupied commercial real estate
Allowance for loan losses:
Beginning balance		4	4
Provision	1,060	188	1,384
Charge-offs			(1,405)
Recoveries	4		17
Ending balance	1,064	192
Loans evaluated for impairment:
Collectively evaluated for impairment				109,193	115,053	154,737
Individually evaluated for impairment				8,743	8,942	739
Purchased credit impaired				5,246	5,339	6,981
Total loans held for investment				123,182	129,334	162,457
Allowance for loans losses evaluated:
Individually evaluated for impairment				1,064		177
Purchased credit impaired						15
Total allowance for loan losses	1,064	4	4	1,064		192
Acquired | Commercial real estate
Allowance for loan losses:
Beginning balance	437	166	166
Provision	(97)	(142)	737
Charge-offs			(466)
Ending balance	340	24	437
Loans evaluated for impairment:
Collectively evaluated for impairment				307,394	314,913	370,130
Individually evaluated for impairment				1,912	2,002	1,555
Purchased credit impaired				10,699	10,807	12,175
Total loans held for investment				320,005	327,722	383,860
Allowance for loans losses evaluated:
Collectively evaluated for impairment				340	429
Purchased credit impaired					8	24
Total allowance for loan losses	437	166	166	340	437	24
Acquired | Construction, land & land development
Allowance for loan losses:
Beginning balance	115	8	8
Provision	(85)	(2)	1,654
Charge-offs	(95)		(1,631)
Recoveries	74	25	84
Ending balance	9	31	115
Loans evaluated for impairment:
Collectively evaluated for impairment				49,478	66,908	94,932
Individually evaluated for impairment				1,336	978
Purchased credit impaired				18	1,819	8,633
Total loans held for investment				50,832	69,705	103,565
Allowance for loans losses evaluated:
Collectively evaluated for impairment				9	14	28
Purchased credit impaired					101	3
Total allowance for loan losses	115	8	8	9	115	31
Acquired | Residential mortgage
Allowance for loan losses:
Beginning balance	685	1	1
Provision	(106)	942	1,125
Charge-offs		(6)	(548)
Recoveries	32	57	107
Ending balance	611	994	685
Loans evaluated for impairment:
Collectively evaluated for impairment				107,036	113,338	151,154
Individually evaluated for impairment				1,296	1,691	1,069
Purchased credit impaired				2,708	2,717	4,072
Total loans held for investment				111,040	117,746	156,295
Allowance for loans losses evaluated:
Collectively evaluated for impairment				594	672	977
Individually evaluated for impairment						17
Purchased credit impaired				17	13
Total allowance for loan losses	685	1	1	611	685	994
Acquired | Consumer and other
Allowance for loan losses:
Beginning balance	12
Provision	199	7	3
Charge-offs			(15)
Recoveries	4	4	24
Ending balance	215	11	12
Loans evaluated for impairment:
Collectively evaluated for impairment				1,655	2,186	3,286
Individually evaluated for impairment				216	5
Total loans held for investment				1,871	2,191	3,286
Allowance for loans losses evaluated:
Collectively evaluated for impairment				7	10	11
Individually evaluated for impairment				208	2
Total allowance for loan losses	$ 12	$ 11	$ 12	$ 215	$ 12	$ 11