Derivative Financial Instruments Part 1 (Details) (USD $)	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Net positive ineffectiveness on MSR fair value		$ 263,000
Net negative ineffectiveness on MSR fair value	1,000,000
Notional amount of mirror-image derivative contracts	94,400,000		71,200,000
Termination value of derivatives	1,700,000		1,800,000
Designated as Hedging Instrument [Member] | Forward Contracts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet obligations	272,000,000		199,500,000
Negative valuation adjustment			2,200,000
Positive valuation adjustment	176,000
Not Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet obligations	169,700,000		117,500,000
Positive valuation adjustment	$ 502,000		$ 702,000