Tax Cuts And Jobs Act Of 2017, Reclassification From AOCI To Retained Earnings Tax Effect

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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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Summary of Significant Accounting Policies - Recent Accounting Developments - Guidance Adopted in 2017 (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase (decrease) in cash flows from operations	$ 1,387	$ 2,088	$ 1,349
Increase (decrease) in cash flows from investing	(1,066)	(792)	(1,528)
Adjustment for adoption of accounting pronouncements	(257)
Decrease in cash flows from financing	485	915	432
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustment for adoption of accounting pronouncements	(286)
Accounting Standards Update 2018-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification from AOCI to retained earnings tax effect	$ 13
Accounting Standards Update 2016-18
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase (decrease) in cash flows from operations		(53)	37
Increase (decrease) in cash flows from investing		32	(43)
Adoption of ASU 2016-16 \| Noncurrent Assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustment for adoption of accounting pronouncements		267
Adoption of ASU 2016-16 \| Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustment for adoption of accounting pronouncements		(267)
Accounting Standards Update 2016-15 \| New Accounting Pronouncement, Early Adoption, Effect
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase (decrease) in cash flows from operations		$ 121
Decrease in cash flows from financing			$ 121