Consolidated Statements of Financial Position (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Cash and cash equivalents:
Cash and cash due from banks	$ 130,811	$ 142,467
Interest-bearing deposits with the Federal Reserve Bank	179,977	513,668
Total cash and cash equivalents	310,788	656,135
Investment securities:
Available-for-sale, at fair value	684,570	586,809
Held-to-maturity, at amortized cost (fair value - $268,271 at December 31, 2013 and $229,922 at December 31, 2012)	273,905	229,977
Total investment securities	958,475	816,786
Loans held-for-sale, at fair value	5,219	17,665
Loans	4,647,621	4,167,735
Allowance for loan losses	(79,072)	(84,491)
Net loans	4,568,549	4,083,244
Premises and equipment	75,308	75,458
Goodwill	120,164	120,164
Other intangible assets	13,424	15,388
Interest receivable and other assets	132,781	132,412
Total Assets	6,184,708	5,917,252
Deposits:
Noninterest-bearing	1,227,768	1,085,857
Interest-bearing	3,894,617	3,835,586
Total deposits	5,122,385	4,921,443
Interest payable and other liabilities	38,395	54,716
Short-term borrowings	327,428	310,463
Federal Home Loan Bank (FHLB) advances	0	34,289
Total liabilities	5,488,208	5,320,911
Shareholders' equity:
Preferred stock, no par value:	0	0
Issued and outstanding — 29,789,825 shares at December 31, 2013 and 27,498,868 shares at December 31, 2012	29,790	27,499
Additional paid in capital	488,177	433,195
Retained earnings	199,053	166,766
Accumulated other comprehensive loss	(20,520)	(31,119)
Total shareholders' equity	696,500	596,341
Total Liabilities and Shareholders' Equity	$ 6,184,708	$ 5,917,252