Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
INTEREST REVENUE:
Loans and leases	$ 419,813	$ 404,559	$ 396,441
Deposits with other banks	438	532	1,694
Available-for-sale securities:
Taxable	26,308	27,755	33,286
Tax-exempt	13,075	14,462	15,547
Loans held for sale	4,744	2,949	2,539
Total interest revenue	464,378	450,257	449,507
Deposits:
Interest bearing demand	8,820	7,851	9,645
Savings	1,703	1,614	1,705
Other time	14,837	20,675	29,729
Federal funds purchased and securities sold under agreement to repurchase	383	331	297
Long-term debt	2,285	2,463	1,803
Junior subordinated debt	667	659	7,376
Other	1	2	3
Total interest expense	28,696	33,595	50,558
Net interest revenue	435,682	416,662	398,949
Provision for credit losses	(13,000)		7,500
Net interest revenue, after provision for credit losses	448,682	416,662	391,449
NONINTEREST REVENUE:
Mortgage lending	35,530	22,671	44,977
Credit card, debit card and merchant fees	36,533	35,303	33,005
Deposit service charges	46,765	50,622	52,905
Security gains, net	136	37	46
Insurance commissions	116,744	114,842	97,700
Wealth management	22,660	23,940	23,576
Other	19,600	21,731	22,857
Total noninterest revenue	277,968	269,146	275,066
NONINTEREST EXPENSE:
Salaries and employee benefits	322,469	307,828	306,696
Occupancy, net of rental income	41,866	41,345	41,109
Equipment	15,309	16,869	18,386
Deposit insurance assessments	9,509	8,190	11,755
Voluntary early retirement expense			10,850
Write-off and amortization of bond issue cost	48	48	2,995
Other	150,710	144,126	143,058
Total noninterest expense	539,911	518,406	534,849
Income before income taxes	186,739	167,402	131,666
Income tax expense	59,248	50,652	37,551
Net Income	$ 127,491	$ 116,750	$ 94,115
Earnings per share: Basic (in dollars per share)	$ 1.33	$ 1.22	$ 0.99
Earnings per share: Diluted (in dollars per share)	$ 1.33	$ 1.21	$ 0.99