Fair Value (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Fair Value Disclosures [Abstract]
Fair value measurements with unobservable inputs, percent of total financial assets	7.00%
Fair value measurements with unobservable inputs, percent of total financial liabilities	1.00%
Percent of level 3 portfolio priced using non-binding broker quotes	98.00%
Percent of level 3 portfolio priced using internal model pricing	2.00%
Assets, level 1 to level 2 transfers	$ 0	$ 0
Assets, level 2 to level 1 transfers	0	0
Liabilities, level 1 to level 2 transfers	0	0
Liabilities, level 2 to level 1 transfers	$ 0	$ 0

Fair Value, Measurement with Unobservable Inputs, Assets, Percent of Total Financial Assets

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- Definition

Fair Value, Measurement with Unobservable Inputs, Liabilities, Percent of Total Financial Liabilities

+ References

No definition available.

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- Definition

Percent of Level 3 Portfolio Priced Using Internal Model Pricing

+ References

No definition available.

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- Definition

Percent of Level 3 Portfolio Priced Using Non-Binding Broker Quotes

+ References

No definition available.

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bb)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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