Consolidated statements of changes in shareholders' equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss), Net
Balance at Dec. 31, 2016	$ 330,498	$ 24,108	$ 213,480	$ 93,784	$ (874)
Initial fair value election on mortgage servicing rights, net of taxes of $396	615			615
Net income	29,380			29,380
Other comprehensive income (loss), net of taxes	2,445				2,445
Common stock issued, net of offering costs	152,721	4,807	147,914
Common stock issued in conjunction with acquisition of the Clayton Banks, net of issuance costs (See Note 2)	52,284	1,521	50,763
Stock-based compensation expense	4,808	9	4,799
Restricted stock units vested and distributed, net of shares withheld for taxes	(858)	63	(921)
Shares issued under employee stock purchase program	635	19	616
Balance at Sep. 30, 2017	572,528	30,527	416,651	123,779	1,571
Balance at Dec. 31, 2017	596,729	30,536	418,596	147,449	148
Initial adoption of ASU 2016-01 (See Note 1)				(109)	109
Net income	63,196			63,196
Other comprehensive income (loss), net of taxes	(11,262)				(11,262)
Stock-based compensation expense	5,327	9	5,318
Restricted stock units vested and distributed, net of shares withheld for taxes	(2,637)	142	(2,779)
Shares issued under employee stock purchase program	1,196	29	1,167
Dividends declared ($0.12 per share)	(3,818)			(3,818)
Balance at Sep. 30, 2018	$ 648,731	$ 30,716	$ 422,302	$ 206,718	$ (11,005)