Mortgage Banking Activities, Components of Loans Held For Sale (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Components of Residential Mortgage Loans Held for Sale [Abstract]
Fair Value	$ 513,196us-gaap_LoansHeldForSaleMortgages	$ 304,182us-gaap_LoansHeldForSaleMortgages	$ 226,512us-gaap_LoansHeldForSaleMortgages
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	90 days
Residential mortgage loans held for sale, nonperforming	0	0	0
Credit losses recognized on residential mortgage loans held for sale	0		0
Components of Residential Mortgage Loans Held for Sale [Abstract]
Unpaid Principal Balance	491,762	291,537	215,959
Fair Value	501,888	298,212	220,074
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	60 days
General number of days outstanding for residential mortgage commitments, maximum (in days)	90 days	90 days	90 days
Components of Residential Mortgage Loans Held for Sale [Abstract]
Notional	650,988	520,829	387,755
Fair Value	17,500	9,971	6,035
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	60 days
General number of days for delivery for loans, for which the price is set by forward sales contracts, maximum (in days)	90 days	90 days	90 days
Components of Residential Mortgage Loans Held for Sale [Abstract]
Notional	1,200,769	701,066	571,458
Fair Value	$ (6,192)	$ (4,001)	$ 403

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Credit losses recognized on residential mortgage loans held for sale

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No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

No definition available.

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- Definition

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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- Definition

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

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

+ References

No definition available.

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- Definition

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

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No definition available.

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- Definition

Unpaid principal balance of loans held for sale.

+ References

No definition available.

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- Definition

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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- Definition

Amount classified as mortgage loans attributable to disposal group held for sale or disposed of. 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

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

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6490309&loc=d3e48678-111004

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Permanent Investor

-URI http://asc.fasb.org/extlink&oid=6520390

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