Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Assets
Cash and due from banks	$ 139,635	$ 157,625
Short-term interest bearing accounts	7,001	1,301
Securities available for sale, at fair value	1,013,171	1,364,881
Securities held to maturity (fair value $454,994 and $113,276)	454,361	117,283
Trading securities	7,793	5,779
Federal Reserve and Federal Home Loan Bank stock	32,626	46,864
Loans	5,595,271	5,406,795
Less allowance for loan losses	66,359	69,434
Net loans	5,528,912	5,337,361
Premises and equipment, net	89,258	88,327
Goodwill	263,634	264,997
Intangible assets, net	20,317	25,557
Bank owned life insurance	114,251	114,966
Other assets	126,967	127,234
Total assets	7,797,926	7,652,175
Liabilities
Demand (noninterest bearing)	1,838,622	1,645,641
Savings, NOW, and money market	3,417,160	3,223,441
Time	1,043,823	1,021,142
Total deposits	6,299,605	5,890,224
Short-term borrowings	316,802	456,042
Long-term debt	130,945	308,823
Junior subordinated debt	101,196	101,196
Other liabilities	85,197	79,321
Total liabilities	6,933,745	6,835,606
Stockholders' equity
Preferred stock, $0.01 par value; authorized 2,500,000 shares at December 31, 2014 and 2013	0	0
Common stock, $0.01 par value. Authorized 100,000,000 shares at December 31, 2014 and December 31, 2013; issued 49,651,494 at December 31, 2014 and December 31, 2013	497	497
Additional paid-in-capital	576,504	574,152
Retained earnings	423,956	385,787
Accumulated other comprehensive loss	(17,027)	(16,765)
Common stock in treasury, at cost, 5,755,040 and 6,138,444 shares at December 31, 2014 and 2013, respectively	(119,749)	(127,102)
Total stockholders' equity	864,181	816,569
Total liabilities and stockholders' equity	$ 7,797,926	$ 7,652,175