Parent Corporation Only Statements (Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Assets
Cash	$ 122,313	$ 91,059	$ 35,889	$ 56,029
Total assets	2,873,894	1,430,708	1,178,548
Liabilities
Total liabilities	2,452,270	1,310,178
Shareholders' Equity
Common stock	17,146	8,881
Capital surplus	307,670	21,779
Retained earnings	98,584	91,439
Accumulated other comprehensive loss	(1,776)	(1,569)
Total shareholders' equity	421,624	120,530	109,138	98,904
Total liabilities and shareholders' equity	2,873,894	1,430,708
Parent [Member]
Assets
Cash	10,949	11,339	$ 9,469	$ 9,985
Investment in subsidiaries	410,981	109,825
Other assets	1,792	585
Total assets	423,722	121,749
Liabilities
Other liabilities	2,098	1,219
Total liabilities	2,098	1,219
Shareholders' Equity
Common stock	17,146	8,881
Capital surplus	307,614	21,779
Retained earnings	98,584	91,439
Accumulated other comprehensive loss	(1,720)	(1,569)
Total shareholders' equity	421,624	120,530
Total liabilities and shareholders' equity	$ 423,722	$ 121,749