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Commitments, Contingencies and Guarantees (Details) $ in Millions | 6 Months Ended
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Jun. 30, 2016 USD ($)
Commitments, Contingencies And Guarantees [Abstract] |
Net Loss from Unsecured Customer Receivables | $ 119

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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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Period Type: | duration

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- References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Balance Type: | na
Period Type: | duration