Commitments, Guarantees, and Contingent Liabilities (Details) - Contractual or Notional Amounts of Financial Instruments - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
Recourse on assets sold: [Abstract]
Unpaid principal balance of loans sold		$ 199,748	$ 185,910
Carrying value of recourse obligation	[1]	76	155
Letter of Credit
Commitments, Guarantees, and Contingent Liabilities (Details) - Contractual or Notional Amounts of Financial Instruments [Line Items]
Standby letters of credit		102,996	110,639
Commitments to Extend Credit
Commitments, Guarantees, and Contingent Liabilities (Details) - Contractual or Notional Amounts of Financial Instruments [Line Items]
Commercial, industrial, and agricultural		1,253,880	1,299,683
Commercial real estate		288,930	170,573
Home equity		336,786	317,783
Other commitments	[2]	201,646	194,556
Total commitments to extend credit		$ 2,081,242	$ 1,982,595

[1] Included in other liabilities in the Consolidated Statements of Financial Condition

[2] Other commitments includes installment and overdraft protection program commitments.