Mortgage Banking Activities, Components of Loans Held For Sale (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Mortgage Banking Activities [Abstract]
General number of days outstanding for residential mortgage commitments, minimum (in days)			60 D
General number of days outstanding for residential mortgage commitments, maximum (in days)			90 D
General number of days for delivery of loans, for which the price is set by forward sales contracts, minimum (in days)			60 D
General number of days for delivery of loans, for which the price is set by forward sales contracts, maximum (in days)			90 D
Number of days for past due loans (in days)			90 D
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Components of Residential Mortgages Held For Sale Gross, Fair Value	$ 169,609	$ 227,574	$ 169,609	$ 227,574	$ 263,413
Mortgage and Marketing Revenue [Abstract]
Total originating and marketing revenue	9,409	8,764	16,938	15,286
Servicing revenue	9,947	9,571	19,774	17,920
Mortgage banking revenue	19,356	18,335	36,712	33,206
Residential Mortgage Loans Held For Sale Gross [Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Components of Residential Mortgages Held For Sale Gross, Fair Value	167,300	229,493	167,300	229,493	254,669
Residential Mortgage Loans Held For Sale Unpaid Principal Balance, Gross	162,579	227,574	162,579	227,574	253,778
Mortgage and Marketing Revenue [Abstract]
Mortgage Loans Held For Sale, Gain (Loss)	10,037	13,528	23,373	21,326
Residential Mortgage Loan Commitments [Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Components of Residential Mortgages Held For Sale Gross, Fair Value	2,793	5,538	2,793	5,538	2,251
Residential Mortgage Derivatives Notional Amount	156,209	189,029	156,209	189,029	138,870
Mortgage and Marketing Revenue [Abstract]
Mortgage Loans Held For Sale, Gain (Loss)	(702)	3,072	542	5,043
Forward Sales Contracts[Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Components of Residential Mortgages Held For Sale Gross, Fair Value	(484)	(7,457)	(484)	(7,457)	6,493
Residential Mortgage Derivatives Notional Amount	302,526	407,457	302,526	407,457	396,422
Mortgage and Marketing Revenue [Abstract]
Mortgage Loans Held For Sale, Gain (Loss)	$ 74	$ (7,836)	$ (6,977)	$ (11,083)

Maximum number of days for delivery of forward sales contracts.

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Maximum number of days outstanding for residential mortgage commitments to purchase.

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Minimum number of days for delivery of forward sales contracts.

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Minimum number of days outstanding for residential mortgage commitments to purchase.

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The noninterest income derived from mortgage banking activities (fees and commissions). This includes fees earned from servicing third-party assets.

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Number of days past due for residential mortgage loans

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Revenue related to fees charged to customers on entering into a loan agreement to cover the cost of processing the loan. Also includes revenue from public relations and corporate promotions.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Income from mortgage banking activities (fees and commissions) and servicing real estate mortgages, credit cards, and other financial assets held by others net of any related impairment of capitalized service costs. Also includes any premiums received in lieu of regular servicing fees on such loans only as earned over the life of the loans.

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The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Carrying amount of mortgage loans to individuals not classified as held for investment but are held-for-sale.

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The carrying amount of the outstanding balance due under the mortgage loan.

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Aggregate notional amount of all derivatives. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

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