Derivative Financial Instruments Notional Amounts and Fair Values of Derivative Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Asset (Liability) Fair Value	$ 5,322	$ 1,167
Interest Rate Lock Commitments [Member]
Asset (Liability) Fair Value	4,687	3,878
Interest Rate Lock Commitments [Member] | Positive Fair Values [Member]
Notional Amount	348,992	181,583
Asset, Fair Value	4,717	3,888
Interest Rate Lock Commitments [Member] | Negative Fair Values [Member]
Notional Amount	3,968	1,593
Liability, Fair Value	(30)	(10)
Forward Commitments [Member]
Asset (Liability) Fair Value	635	(2,711)
Forward Commitments [Member] | Positive Fair Values [Member]
Notional Amount	307,865	3,178
Asset, Fair Value	733	13
Forward Commitments [Member] | Negative Fair Values [Member]
Notional Amount	46,956	173,208
Liability, Fair Value	$ (98)	$ (2,724)