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Commitments, Contingencies and Guarantees (Details) $ in Millions	9 Months Ended
	Sep. 30, 2016 USD ($)
Commitments, Contingencies And Guarantees [Abstract]
Net Loss from Unsecured Customer Receivables	$ 118

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- Definition

Net loss from unsecured customer receivables due to the sudden move in the value of the Swiss franc that followed an unprecedented action by the Swiss National Bank in January of 2015.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

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- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration