Mortgage Banking Activities, Components of Loans Held For Sale (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Components of Residential Mortgages Held For Sale Gross, Fair Value	$ 200,546	$ 293,762
Mortgage Banking Revenue [Abstract]
Total originating and marketing revenue	79,545	129,117	51,982
Servicing revenue	42,389	40,185	39,661
Mortgage banking revenue	121,934	169,302	91,643
Residential mortgage loans held for sale [Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Number of days for past due for loan to be considered nonperforming (in days)	90 days	90 days
Residential mortgage loans held for sale, nonperforming	0	0
Credit losses recognized on residential mortgage loans held for sale	0	0
Residential mortgage loans held for sale, Unpaid Principal Balance	192,266	269,718
Components of Residential Mortgages Held For Sale Gross, Fair Value	193,584	281,935
Mortgage Banking Revenue [Abstract]
Total originating and marketing revenue	84,403	120,599	57,418
Residential mortgage loan commitments [Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
General number of days outstanding for residential mortgage commitments, minimum (in days)	60 days	60 days
General number of days outstanding for residential mortgage commitments, maximum (in days)	90 days	90 days
Residential mortgage, Derivative contracts, Notional	258,873	356,634
Components of Residential Mortgages Held For Sale Gross, Fair Value	2,656	12,733
Mortgage Banking Revenue [Abstract]
Total originating and marketing revenue	(10,070)	6,136	4,345
Forward sales contracts[Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
General number of days for delivery of loans, for which the price is set by forward sales contracts, minimum (in days)	60 days	60 days
General number of days for delivery of loans, for which the price is set by forward sales contracts, maximum (in days)	90 days	90 days
Residential mortgage, Derivative contracts, Notional	435,867	598,442
Components of Residential Mortgages Held For Sale Gross, Fair Value	4,306	(906)
Mortgage Banking Revenue [Abstract]
Total originating and marketing revenue	$ 5,212	$ 2,382	$ (9,781)

Credit losses recognized on residential mortgage loans held for sale

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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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Noninterest income derived from the sale and changes in fair value of residential mortgage loans held for sale and fees for servicing of residential mortgage loans held by third parties. Also includes changes in the fair value of residential mortgage loan commitments and forward sales commitments considered to be derivative instruments.

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Number of days past due for residential mortgage loans

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Total gain (loss) on mortgage loans held for sale, including mortgage loan commitments and forward sales contracts.

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No definition available.

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Residential mortgage loans held for sale, 90 days past due or impaired.

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Unpaid principal balance of loans held for sale.

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Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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Amount of mortgage loans held for sale. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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-SubTopic 210

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Amount of revenue from servicing real estate mortgages, credit cards, and other financial assets held by others. Includes premiums received in lieu of regular servicing fees.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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