Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Interest income
Interest and fees on loans	$ 132,485	$ 74,401
Interest on investment securities:
Taxable	4,756	1,929
Tax-exempt	4,235	2,665
Dividends on nonmarketable equity securities	621	256
Interest on deposits with the Federal Reserve Bank, other banks and Federal funds sold	799	213
Total interest income	142,896	79,464
Interest expense
Interest on deposits	8,916	4,059
Interest on short-term borrowings	1,658	100
Interest on long-term borrowings	2,225	975
Total interest expense	12,799	5,134
Net interest income	130,097	74,330
Provision for loan losses	4,050	1,500
Net interest income after provision for loan losses	126,047	72,830
Noninterest income
Service charges and fees on deposit accounts	8,004	5,720
Wealth management revenue	5,827	5,201
Other charges and fees for customer services	8,891	6,392
Mortgage banking revenue	9,160	1,405
Gain on sale of investment securities	90	19
Other	6,038	682
Total noninterest income	38,010	19,419
Operating expenses
Salaries, wages and employee benefits	60,248	33,890
Occupancy	7,392	4,905
Equipment and software	8,517	4,404
Merger and acquisition-related transaction expenses	4,167	2,594
Other	23,872	13,094
Total operating expenses	104,196	58,887
Income before income taxes	59,861	33,362
Income tax expense	12,257	9,757
Net income	$ 47,604	$ 23,605
Earnings per common share:
Basic (in dollars per share)	$ 0.67	$ 0.61
Diluted (in dollars per share)	0.67	0.60
Cash dividends declared per common share (in dollars per share)	$ 0.27	$ 0.26