Loan Sales And Securitizations (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Loan Sales And Securitizations [Abstract]
Single-family residential mortgage loans transferred	$ 53.4	$ 138.2
Net pre-tax gains on sale of residential mortgage loan	$ 0.9	$ 2.6
Percentage of single-family mortgage loans received as fees	0.29%	0.29%
Percentage of outstanding balance generating for annual servicing inclusive excess interests	0.34%	0.34%
Percentage of HELOC and home equity loans received as fees	0.50%	0.50%
Percentage variation in assumptions that can not necessarily be extrapolated	10.00%

Percentage Of Outstanding Balance Generating For Annual Servicing

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- Definition

Percentage Of Outstanding Balance Generating For Annual Servicing Including Excess Interests

+ References

No definition available.

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- Definition

Percentage of outstanding balances of HELOC and home equity loans transferred that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer.

+ References

No definition available.

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- Definition

Percentage variation in assumptions that can not necessarily be extrapolated

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No definition available.

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- Definition

Total UPB of Single-Family Residential Mortgage Loans managed through whole loans sales or securitizations.

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No definition available.

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- Definition

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.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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