Allowance For Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Allowance for loan losses:
Beginning balance	$ 32,947	$ 15,605	$ 15,605
Charge-offs	(9,906)	(182)		$ (2,856)
Recoveries	673	614	2,334
Provision	16,000	1,505	17,864
Ending balance	39,714	17,542	32,947	15,605
Collectively evaluated for impairment					$ 26,227	$ 17,898	$ 433
Individually evaluated for impairment					13,435	14,840	16,187
Purchased credit impaired					52	209	922
Total allowance for loan losses	32,947	15,605	15,605	15,605	39,714	32,947	17,542
Loans receivable:
Collectively evaluated for impairment					3,069,380	3,039,502	9,292
Individually evaluated for impairment					56,151	44,993	1,788,141
Purchased credit impaired					42,652	46,174	13,409
Total loans held for investment					3,168,183	3,130,669	1,810,842
Commercial & Industrial [Member]
Allowance for loan losses:
Beginning balance	23,130	8,145	8,145
Charge-offs	(9,880)	(77)		(2,647)
Recoveries	582	597	2,185
Provision	10,899	(25)	15,447
Ending balance	24,731	8,640	23,130	8,145
Collectively evaluated for impairment					11,580	8,352	261
Individually evaluated for impairment					13,141	14,733	7,625
Purchased credit impaired					10	45	754
Total allowance for loan losses	23,130	8,145	8,145	8,145	24,731	23,130	8,640
Loans receivable:
Collectively evaluated for impairment					1,074,993	1,157,464	3,643
Individually evaluated for impairment					44,926	35,083	738,682
Purchased credit impaired					10,791	13,905	2,055
Total loans held for investment					1,130,710	1,206,452	744,380
Owner occupied commercial real estate [Member]
Allowance for loan losses:
Beginning balance	1,679	974	974
Provision	596	334	705
Ending balance	2,275	1,308	1,679	974
Collectively evaluated for impairment					2,083	1,677
Individually evaluated for impairment					177		1,305
Purchased credit impaired					15	2	3
Total allowance for loan losses	1,679	974	974	974	2,275	1,679	1,308
Loans receivable:
Collectively evaluated for impairment					358,997	345,911	1,029
Individually evaluated for impairment					1,529	829	164,512
Purchased credit impaired					6,981	7,149	1,063
Total loans held for investment					367,507	353,889	166,604
Commerical real estate [Member]
Allowance for loan losses:
Beginning balance	4,691	2,942	2,942
Recoveries		1	77
Provision	2,533	923	1,672
Ending balance	7,224	3,866	4,691	2,942
Collectively evaluated for impairment					7,200	4,537
Individually evaluated for impairment							3,712
Purchased credit impaired					24	154	154
Total allowance for loan losses	4,691	2,942	2,942	2,942	7,224	4,691	3,866
Loans receivable:
Collectively evaluated for impairment					1,001,376	884,881	547
Individually evaluated for impairment					6,848	6,946	359,379
Purchased credit impaired					12,175	12,288	7,145
Total loans held for investment					1,020,399	904,115	367,071
Construction, land & land development [Member]
Allowance for loan losses:
Beginning balance	2,345	2,633	2,633
Recoveries	26		5
Provision	497	(164)	(293)
Ending balance	2,868	2,469	2,345	2,633
Collectively evaluated for impairment					2,779	2,245
Individually evaluated for impairment					86	92	2,458
Purchased credit impaired					3	8	11
Total allowance for loan losses	2,345	2,633	2,633	2,633	2,868	2,345	2,469
Loans receivable:
Collectively evaluated for impairment					347,116	349,660	2,430
Individually evaluated for impairment					458	472	270,638
Purchased credit impaired					8,633	8,681	57
Total loans held for investment					356,207	358,813	273,125
Residential mortgage [Member]
Allowance for loan losses:
Beginning balance	816	645	645
Charge-offs	(6)			(63)
Recoveries	57	12	36
Provision	1,371	398	198
Ending balance	2,238	1,055	816	645
Collectively evaluated for impairment					2,207	801	172
Individually evaluated for impairment					31	15	883
Total allowance for loan losses	816	645	645	645	2,238	816	1,055
Loans receivable:
Collectively evaluated for impairment					273,942	287,843	1,491
Individually evaluated for impairment					2,222	1,489	245,011
Purchased credit impaired					4,072	4,151	3,089
Total loans held for investment					280,236	293,483	249,591
Consumer and other [Member]
Allowance for loan losses:
Beginning balance	286	266	266
Charge-offs	(20)	(105)		(146)
Recoveries	8	4	31
Provision	104	39	135
Ending balance	378	204	286	266
Collectively evaluated for impairment					378	286
Individually evaluated for impairment							204
Total allowance for loan losses	$ 286	$ 266	$ 266	$ 266	378	286	204
Loans receivable:
Collectively evaluated for impairment					12,956	13,743	152
Individually evaluated for impairment					168	174	9,919
Total loans held for investment					$ 13,124	$ 13,917	$ 10,071