CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
INTEREST INCOME
Loans	$ 251,027	$ 157,935	$ 111,097
Investment securities and other interest-earning assets	18,978	8,670	7,259
Total interest income	270,005	166,605	118,356
INTEREST EXPENSE
Deposits	13,371	8,391	6,630
FHLB advances and other borrowings	4,411	1,295	1,490
Subordinated debentures	4,721	3,844	3,937
Total interest expense	22,503	13,530	12,057
Net interest income before provision for loan losses	247,502	153,075	106,299
Provision for loan losses	8,640	8,776	6,425
Net interest income after provision for loan losses	238,862	144,299	99,874
NONINTEREST INCOME
Loan servicing fees	787	1,032	371
Deposit fees	3,809	1,697	1,274
Net gain from sales of loans	12,468	9,539	7,970
Net gain from sales of investment securities	2,737	1,797	290
Other income	11,313	5,537	4,483
Total noninterest income	31,114	19,602	14,388
NONINTEREST EXPENSE
Compensation and benefits	84,138	52,836	37,108
Premises and occupancy	14,742	9,838	7,810
Data processing	8,206	4,261	2,816
Other real estate owned operations, net	72	385	68
FDIC insurance premiums	2,151	1,545	1,376
Legal, audit and professional expense	6,101	3,041	2,514
Marketing expense	4,436	3,981	2,305
Office, telecommunications and postage expense	3,117	2,107	2,005
Loan expense	3,299	2,191	1,268
Deposit expense	6,240	4,904	3,643
Merger-related expense	21,002	4,388	4,799
CDI amortization	6,144	2,039	1,350
Other expense	8,102	7,067	6,476
Total noninterest expense	167,750	98,583	73,538
Net income before income taxes	102,226	65,318	40,724
Income tax	42,126	25,215	15,209
Net income	$ 60,100	$ 40,103	$ 25,515
EARNINGS PER SHARE
Basic (in dollars per share)	$ 1.59	$ 1.49	$ 1.21
Diluted (in dollars per share)	$ 1.56	$ 1.46	$ 1.19
WEIGHTED AVERAGE SHARES OUTSTANDING
Basic (in shares)	37,705,556	26,931,634	21,156,668
Diluted (in shares)	38,511,261	27,439,159	21,488,698