Mortgage Banking Activities, Components of Loans Held For Sale (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Components of Residential Mortgages Held For Sale Gross, Fair Value	$ 325,875	$ 200,546	$ 301,057	$ 325,875	$ 301,057
Mortgage Banking Revenue [Abstract]
Production revenue	17,727		26,356	29,179	56,266
Servicing revenue	11,603		10,240	22,995	20,306
Mortgage banking revenue	29,330		36,596	52,174	76,572
Residential Mortgage Loans Held For Sale [Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Residential Mortgage Loans Held For Sale Unpaid Principal Balance/Notional	310,341	192,266	284,454	310,341	284,454
Components of Residential Mortgages Held For Sale Gross, Fair Value	319,508	193,584	280,962	319,508	280,962
Number of days for past due loans (in days)	90 days	90 days	90 days
Residential mortgage loans held for sale, nonperforming	0	0	0	0	0
Credit losses recognized on residential mortgage loans held for sale				0	0
Mortgage Banking Revenue [Abstract]
Production revenue	17,764		17,763	29,732	47,998
Residential Mortgage Loan Commitments [Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Residential Mortgage, Derivatives, Notional	546,864	258,873	547,508	546,864	547,508
Components of Residential Mortgages Held For Sale Gross, Fair Value	13,616	2,656	(1,709)	13,616	(1,709)
Minimum Number of Days Outstanding For Residential Mortgage Commitments	60 days	60 days	60 days
Maximum Number of Days Outstanding For Residential Mortgage Commitments	90 days	90 days	90 days
Mortgage Banking Revenue [Abstract]
Production revenue	7,614		(15,052)	11,001	(14,442)
Forward Sales Contracts [Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Residential Mortgage, Derivatives, Notional	828,739	435,867	740,752	828,739	740,752
Components of Residential Mortgages Held For Sale Gross, Fair Value	(7,249)	4,306	21,804	(7,249)	21,804
Minimum Number of Days for Delivery of Forward Sales Contracts	60 days	60 days	60 days
Maximum Number of Days for Delivery of Forward Sales Contracts	90 days	90 days	90 days
Mortgage Banking Revenue [Abstract]
Production revenue	$ (7,651)		$ 23,645	$ (11,554)	$ 22,710

Credit losses recognized on residential mortgage loans held for sale

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Represents represents the typical maximum number of days from the point pricing is set to delivery of forward sales contracts.

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Represents represents the typical maximum period for commitment to originate a residential mortgage loan to when the closed loan is sold to an investor.

+ References

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Represents the minimum number of days from the point of pricing being set to delivery of forward sales contracts.

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No definition available.

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Represents represents the typical minimum period for commitment to originate a residential mortgage loan to when the closed loan is sold to an investor.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Represents the number of days past due for residential mortgage loans held for sale to be reported as delinquent.

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No definition available.

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

+ References

No definition available.

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

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No definition available.

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Unpaid principal balance of loans held for sale.

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No definition available.

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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.

+ References

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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-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(a)(3))

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-Glossary Permanent Investor

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- Definition

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.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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-Subparagraph (SX 210.9-04.13 (d))

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