Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest income:
Loans	$ 170,588	$ 122,962	$ 77,694
Mortgage-backed securities	11,108	6,697	6,051
Investment securities and other	7,133	3,766	2,118
Total interest income	188,829	133,425	85,863
Interest expense:
Deposits	12,336	7,517	4,301
Borrowed funds	7,275	5,646	4,733
Total interest expense	19,611	13,163	9,034
Net interest income	169,218	120,262	76,829
Provision for loan losses	4,445	2,623	1,275
Net interest income after provision for loan losses	164,773	117,639	75,554
Other income:
Bankcard services revenue	6,965	4,833	3,537
Wealth management revenue	2,150	2,324	2,187
Fees and service charges	15,058	10,758	8,392
Net loss from other real estate operations	(874)	(856)	(149)
Income from Bank Owned Life Insurance	3,299	2,230	1,501
Other	474	1,123	958
Total other income	27,072	20,412	16,426
Operating expenses:
Compensation and employee benefits	60,100	47,105	31,946
Occupancy	10,657	8,332	5,722
Equipment	6,769	5,104	3,725
Marketing	2,678	1,882	1,516
Federal deposit insurance	2,564	2,825	2,072
Data processing	8,849	7,577	4,731
Check card processing	3,561	2,210	1,815
Professional fees	3,995	2,848	1,865
Other operating expense	10,810	7,676	5,484
Amortization of core deposit intangible	2,039	623	21
Federal Home Loan Bank advance prepayment fee		136	0
Branch consolidation expenses	6,205		0
Merger related expenses	8,293	16,534	1,878
Total operating expenses	126,520	102,852	60,775
Income before provision for income taxes	65,325	35,199	31,205
Provision for income taxes	22,855	12,153	10,883
Net income	$ 42,470	$ 23,046	$ 20,322
Basic earnings per share (in dollars per share)	$ 1.32	$ 1.00	$ 1.22
Diluted earnings per share (in dollars per share)	$ 1.28	$ 0.98	$ 1.21
Average basic shares outstanding	32,113	23,093	16,600
Average diluted shares outstanding	33,125	23,526	16,811