Fair Value of Derivative Instruments and Hedging Activities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Derivative Instruments and Hedging Activities
Asset Derivatives, Fair Value	$ 23,559	$ 15,050
Liability Derivatives, Fair Value	5,056	2,758
Derivatives Designated as Hedging Instruments
Derivative Instruments and Hedging Activities
Asset Derivatives, Fair Value	1,746	1,631
Liability Derivatives, Fair Value	2,754	2,163
Derivatives Designated as Hedging Instruments | Forward loan sales commitments | Accrued Interest Receivable and Other Assets
Derivative Instruments and Hedging Activities
Asset Derivatives, Fair Value	1,746	1,631
Derivatives Designated as Hedging Instruments | Forward loan sales commitments | Accrued Interest Payable and Other Liabilities
Derivative Instruments and Hedging Activities
Liability Derivatives, Fair Value	2,754	2,163
Derivatives Not Designated as Hedging Instruments
Derivative Instruments and Hedging Activities
Asset Derivatives, Fair Value	21,813	13,419
Liability Derivatives, Fair Value	2,302	595
Derivatives Not Designated as Hedging Instruments | Rate Lock and Forward Loan Sales Commitments | Accrued Interest Receivable and Other Assets
Derivative Instruments and Hedging Activities
Asset Derivatives, Fair Value	19,634	12,857
Derivatives Not Designated as Hedging Instruments | Rate Lock and Forward Loan Sales Commitments | Accrued Interest Payable and Other Liabilities
Derivative Instruments and Hedging Activities
Liability Derivatives, Fair Value	2,179	562
Derivatives Not Designated as Hedging Instruments | Rate Lock Commitments | Accrued Interest Receivable and Other Assets
Derivative Instruments and Hedging Activities
Asset Derivatives, Fair Value	2,179	562
Derivatives Not Designated as Hedging Instruments | Rate Lock Commitments | Accrued Interest Payable and Other Liabilities
Derivative Instruments and Hedging Activities
Liability Derivatives, Fair Value	$ 123	$ 33