Consolidated Statements of Income and Comprehensive Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Interest income
Interest and fees on loans	$ 112,401	$ 73,267
Interest on taxable securities	9,043	5,207
Interest on nontaxable securities	156	322
Interest on deposits in other banks and federal funds sold	3,329	716
Total interest income	124,929	79,512
Interest expense
Interest on deposits	21,684	6,772
Interest on other borrowings	3,850	3,939
Total interest expense	25,534	10,711
Net interest income	99,395	68,801
Provision for loan losses	3,408	1,801
Net interest income after provision for loan losses	95,987	67,000
Noninterest income
Service charges on deposit accounts	11,646	10,228
Mortgage banking activity	13,828	11,900
Other service charges, commissions and fees	768	719
Gain on securities	66	37
Other noninterest income	4,463	3,580
Total noninterest income	30,771	26,464
Noninterest expense
Salaries and employee benefits	38,370	32,089
Occupancy and equipment expense	8,204	6,198
Data processing and communications costs	8,391	7,135
Credit resolution-related expenses	911	549
Advertising and marketing expense	1,741	1,229
Amortization of intangible assets	3,132	934
Merger and conversion charges	2,057	835
Other noninterest expenses	12,619	10,129
Total noninterest expense	75,425	59,098
Income before income tax expense	51,333	34,366
Income tax expense	11,428	7,706
Net income	39,905	26,660
Other comprehensive income (loss)
Net unrealized holding gains (losses) arising during period on investment securities available for sale, net of tax expense (benefit) of $1,028 and ($2,500)	3,867	(9,403)
Reclassification adjustment for gains on investment securities included in earnings, net of tax of ($12) and ($8)	(46)	(29)
Unrealized gains (losses) on cash flow hedges arising during period, net of tax expense (benefit) of ($46) and $75	(173)	281
Other comprehensive income (loss)	3,648	(9,151)
Total comprehensive income	$ 43,553	$ 17,509
Basic earnings per common share (in dollars per share)	$ 0.84	$ 0.70
Diluted earnings per common share (in dollars per share)	0.84	0.70
Dividends declared per common share (in dollars per share)	$ 0.10	$ 0.10
Weighted average common shares outstanding (in thousands)
Basic (in shares)	47,366	37,967
Diluted (in shares)	47,456	38,250