Contingencies, Commitments and Guarantees (Guarantees - Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Contingencies, Commitments and Guarantees (Textuals) [Abstract]
Cumulative maximum indemnities and guarantees contractual limitation	$ 208
Liabilities for indemnities, guarantees and commitments	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	$ 203

Contingencies, Commitments and Guarantees.

No definition available.

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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=82913245&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=82913245&loc=d3e12069-110248

+ Details

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