Summary of Accounting Policies - Risk Management Activities (Details) - Foreign Exchange Forward - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Fair value of derivative asset	$ 1
Fair value of derivative liability		$ 1

Aggregate fair value of all derivative assets designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611

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- Definition

Aggregate fair value of all derivative liabilities designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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