Derivative Financial Instruments Balance sheet category and fair values of derivative instruments (not designated as hedging instruments) (Details) (Not Designated as Hedging Instrument, USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Interest Rate Lock Commitments
Derivatives, Fair Value [Line Items]
Notional Amount	$ 316,351	$ 113,438
Interest Rate Cap
Derivatives, Fair Value [Line Items]
Notional Amount	20,000	20,000
Forward Contracts
Derivatives, Fair Value [Line Items]
Notional Amount	53,326	91,750
Notional Amount	316,571
Other Assets | Interest Rate Lock Commitments
Derivatives, Fair Value [Line Items]
Fair Value	11,011	3,697
Other Assets | Interest Rate Cap
Derivatives, Fair Value [Line Items]
Fair Value	0	0
Other Assets | Forward Contracts
Derivatives, Fair Value [Line Items]
Fair Value	214	(869)
Other Liabilities | Forward Contracts
Derivatives, Fair Value [Line Items]
Fair Value	$ (3,217)