Contingencies, Commitments and Guarantees (Guarantees - Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Contingencies, Commitments and Guarantees (Textuals) [Abstract]
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 228
Guarantor Obligations, Current Carrying Value	2	$ 2
Minimum
Contingencies, Commitments and Guarantees (Textuals) [Abstract]
Indemnities and guarantees contractual limitation range	6
Maximum
Contingencies, Commitments and Guarantees (Textuals) [Abstract]
Indemnities and guarantees contractual limitation range	$ 222

Contingencies, Commitments and Guarantees.

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- Definition

The range of the contractual limitation for guarantees and indemnities.

+ References

No definition available.

+ Details

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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