Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Change in fair value of available-for-sale securities, income tax	$ 0	$ 0
Available-for-sale securities, reclassification to earnings, income tax	0	0
Foreign currency translation adjustments, income tax	(1)	0
Foreign currency, reclassification to earnings, income tax	0	0
Change in derivative fair value, income tax	8	21
Derivative reclassification to earnings, income tax	(1)	3
Pension, amortization of net actuarial gain (loss), income tax	(3)	(1)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost (Credit), Tax	0	0
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Tax	$ 0	$ 0

Amount of tax expense (benefit) related to (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580

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Amount of tax expense (benefit), before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for translation gain (loss) realized upon the sale or liquidation of an investment in a foreign entity and foreign currency hedges that are designated and qualified as hedging instruments for hedges of the foreign currency exposure of a net investment in a foreign operation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of tax (expense) benefit related to cost (credit) of benefit changes attributable to plan participants' prior service resulting from a plan amendment or plan initiation that has not been recognized in net periodic benefit cost (credit).

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

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Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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-Publisher FASB
-Name Accounting Standards Codification
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