Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Interest income
Interest and fees on loans	$ 172,686	$ 148,771	$ 494,892	$ 422,570
Interest on investment securities:
Taxable	16,360	9,326	43,485	21,207
Tax-exempt	6,178	4,577	17,732	13,238
Dividends on nonmarketable equity securities	1,368	1,039	5,458	2,906
Interest on deposits with the Federal Reserve Bank, other banks and Federal funds sold	1,785	1,231	4,326	3,052
Total interest income	198,377	164,944	565,893	462,973
Interest expense
Interest on deposits	27,250	12,926	62,874	32,424
Interest on collateralized customer deposits	721	462	1,886	808
Interest on short-term borrowings	9,510	6,129	28,084	12,100
Interest on long-term borrowings	1,415	1,799	4,168	5,968
Total interest expense	38,896	21,316	97,012	51,300
Net interest income	159,481	143,628	468,881	411,673
Provision for loan losses	6,028	5,499	21,856	15,778
Net interest income after provision for loan losses	153,453	138,129	447,025	395,895
Noninterest income
Net gain on sale of loans and other mortgage banking revenue	9,837	5,241	31,216	24,280
Net gain on sale of investment securities	0	1	3	168
Other	7,372	4,921	22,357	17,102
Total noninterest income	37,917	32,122	116,489	111,700
Operating expenses
Salaries, wages and employee benefits	56,894	52,590	168,599	164,731
Occupancy	8,620	6,871	24,310	23,008
Equipment and software	8,185	7,582	24,120	24,248
Outside processing and service fees	12,660	9,626	33,689	26,061
Merger expenses	0	2,379	0	7,011
Restructuring expenses	0	18,824	0	18,824
Other	23,302	21,667	65,114	58,089
Total operating expenses	109,661	119,539	315,832	321,972
Income before income taxes	81,709	50,712	247,682	185,623
Income tax expense	11,312	10,253	36,701	45,546
Net income	$ 70,397	$ 40,459	$ 210,981	$ 140,077
Earnings per common share:
Basic earnings per common share (dollars per share)	$ 0.99	$ 0.57	$ 2.96	$ 1.98
Diluted earnings per common share (dollars per share)	0.98	0.56	2.93	1.95
Cash dividends declared per common share (dollars per share)	$ 0.34	$ 0.28	$ 0.9	$ 0.82
Service charges and fees on deposit accounts
Noninterest income
Noninterest income	$ 8,187	$ 9,147	$ 25,265	$ 25,928
Wealth management revenue
Noninterest income
Noninterest income	6,040	6,188	19,539	18,973
Other charges and fees for customer services
Noninterest income
Noninterest income	$ 6,481	$ 6,624	$ 18,109	$ 25,249