Mortgage Banking (Details) (USD $)	1 Months Ended	3 Months Ended	6 Months Ended
Dec. 31, 2010	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Mortgage Banking [Abstract]
Balance at beginning of period				$ 51,151,000	$ 50,513,000
Origination of servicing assets				6,380,000	7,930,000
Disposals of mortgage loans sold serviced released				0	(1,157,000)
Due to market changes				(4,674,000)	(11,698,000)
Due to runoff				(2,746,000)	(2,544,000)
Balance at end of period	51,151,000	50,111,000	43,044,000	50,111,000	43,044,000
Gain (Loss) on Fair Value Hedge Ineffectiveness, Net		1,700,000	3,700,000	2,000,000	4,700,000
Proceeds from sale of loans serviced for others					920,900,000
Reduction in Fair Value of MSR's due to sale of assets serviced					8,500,000
Payments to acquire loans receivable	53,900,000
Mortgage loan servicing representation and warranty expenses incurred				1,100,000	620,000
Accrual for mortgage loan servicing representation and warranty expenses	$ 900,000	$ 1,000,000		$ 1,000,000

The amount of accrual for mortgage loan servicing putback expenses from representations and warranties on loans sold.

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Decrease in servicing assets subsequently measured at fair value resulting from conveyance of assets serviced for others.

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The amount of mortgage loan servicing put back expenses from representations and warranties on loans sold.

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Increase during the reporting period in the cumulative value of servicing rights. This increase is the result of new servicing rights that are created when mortgages are sold or transferred. Excludes disposals of mortgage loans sold serviced released.

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Cash inflow resulting from the sale of loans serviced for others.

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The net increase or decrease in fair value as a result of changes in the assumptions or model used to calculate the fair value of servicing assets.

+ References

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-Name Accounting Standards Codification
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Net gain (loss) recognized in earnings during the reporting period representing the amount of the fair value of the hedges' ineffectiveness.

+ References

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- Definition

The cash outflow for the purchase of loan receivable arising from the financing of goods and services.

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- Definition

Fair value as of the balance sheet date of an asset representing net future revenues from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

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The net increase or decrease in fair value as a result of changes in the inputs used to calculate the fair value of servicing assets.

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Decrease in servicing assets subsequently measured at fair value resulting from conveyance of servicing rights to unrelated parties.

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