Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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No definition available.

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Summary of Significant Accounting Policies - Guidance Adopted in 2017 (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Jun. 30, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase (decrease) in cash flow from operations		$ 74	$ 811
Decrease in cash flow from investing		545	470
Decrease in cash flow from financing		(18)	530
ASU 2016-18
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase (decrease) in cash flow from operations			(54)
Decrease in cash flow from investing			$ 1
ASU 2016-16 \| Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustments for change in accounting pronouncement	$ (267)
ASU 2016-16 \| Noncurrent Assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustments for change in accounting pronouncement	$ 267
ASU 2016-15
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase (decrease) in cash flow from operations		55
Decrease in cash flow from financing		$ 55