Segment Reporting - Schedule of Segment Financial Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net interest income	$ 110,950	$ 93,872	$ 83,376
Provision for loan losses	(1,479)	(3,064)	(2,716)
Mortgage banking income	117,751	70,190	31,135
Other noninterest income	26,934	22,190	19,667
Depreciation and amortization	3,995	3,283	3,099
Amortization of intangibles	2,132	1,731	1,613
Amortization and impairment of mortgage servicing rights	12,999	2,795	397
Loss on sale of mortgage servicing rights	4,447
Other noninterest mortgage banking expense	82,351	56,138	29,569
Other noninterest expense	88,866	74,545	67,485
Income before income taxes	62,324	50,824	34,731
Income tax expense	21,733	2,968	2,269
Net income	40,591	47,856	32,462
Total assets	3,276,881	2,899,420	2,428,189
Goodwill	46,867	46,904	46,904
Banking Segment
Segment Reporting Information [Line Items]
Net interest income	112,365	92,366	83,192
Provision for loan losses	(1,479)	(3,070)	(2,716)
Mortgage banking income	25,542	18,718	8,958
Other noninterest income	26,934	22,190	19,667
Depreciation and amortization	3,506	2,933	2,784
Amortization of intangibles	2,132	1,731	1,613
Other noninterest mortgage banking expense	16,095	13,189	8,551
Other noninterest expense	88,866	74,545	67,485
Income before income taxes	55,721	43,946	34,100
Total assets	2,752,773	2,570,071	2,202,978
Goodwill	46,767	46,804	46,804
Mortgage Segment
Segment Reporting Information [Line Items]
Net interest income	(1,415)	1,506	184
Provision for loan losses		6
Mortgage banking income	92,209	51,472	22,177
Depreciation and amortization	489	350	315
Amortization and impairment of mortgage servicing rights	12,999	2,795	397
Loss on sale of mortgage servicing rights	4,447
Other noninterest mortgage banking expense	66,256	42,949	21,018
Income before income taxes	6,603	6,878	631
Total assets	524,108	329,349	225,211
Goodwill	$ 100	$ 100	$ 100