Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Interest income
Loans and leases	$ 216,404	$ 210,862
Investment securities:
Total investment securities interest and dividend income	23,042	19,310
Overnight investments	3,666	1,338
Total interest income	243,112	231,510
Interest expense
Deposits	4,659	5,629
Short-term borrowings	434	1,934
Long-term obligations	5,299	3,782
Total interest expense	10,392	11,345
Net interest income	232,720	220,165
Provision (credit) for loan and lease losses	4,843	5,792
Net interest income after provision for loan and lease losses	227,877	214,373
Noninterest income
Gain on acquisition	1,704	42,930
Cardholder services	19,358	18,401
Merchant services	21,977	18,880
Service charges on deposit accounts	21,850	22,058
Wealth management services	19,634	20,880
Securities gains (losses)	4,628	5,126
Other service charges and fees	6,989	5,455
Mortgage income	1,311	4,549
Insurance commissions	3,178	3,297
ATM income	1,765	1,664
Adjustments for FDIC receivable for loss share agreements	(2,533)	(1,047)
Other	5,421	8,560
Total noninterest income	105,282	150,753
Noninterest expense
Salaries and wages	103,899	105,471
Employee benefits	27,350	31,218
Occupancy expense	25,012	25,620
Equipment expense	22,345	23,541
FDIC insurance expense	4,789	4,271
Foreclosure-related expenses	1,731	2,557
Merger-related expenses	38	2,997
Other	66,507	62,491
Total noninterest expense	251,671	258,166
Income before income taxes	81,488	106,960
Income taxes	29,416	39,802
Net income	$ 52,072	$ 67,158
Average shares outstanding (in shares)	12,010,405	12,010,405
Net income per share	$ 4.34	$ 5.59