Shareholders' Equity (Details 2) $ in Millions	3 Months Ended
Mar. 31, 2016 USD ($)
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ (3,423)
Other comprehensive (loss) income before reclassifications, net	(305)
Amounts reclassified from accumulated other comprehensive loss:
Amounts reclassified from accumulated other comprehensive loss	25
Tax benefit	(7)
Amounts reclassified from accumulated other comprehensive loss, net	18
Net current period other comprehensive (loss) income	(287)
Ending balance	(3,710)
Change in Fair Value of Financial Instruments [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(25)
Other comprehensive (loss) income before reclassifications, net	(7)
Amounts reclassified from accumulated other comprehensive loss:
Amounts reclassified from accumulated other comprehensive loss	(1)
Tax benefit	1
Amounts reclassified from accumulated other comprehensive loss, net	0
Net current period other comprehensive (loss) income	(7)
Ending balance	(32)
Foreign Currency Translation Adjustments [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(771)
Other comprehensive (loss) income before reclassifications, net	(79)
Amounts reclassified from accumulated other comprehensive loss:
Amounts reclassified from accumulated other comprehensive loss	0
Tax benefit	0
Amounts reclassified from accumulated other comprehensive loss, net	0
Net current period other comprehensive (loss) income	(79)
Ending balance	(850)
Post-Retirement Benefit Obligation [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(2,627)
Other comprehensive (loss) income before reclassifications, net	(219)
Amounts reclassified from accumulated other comprehensive loss:
Amounts reclassified from accumulated other comprehensive loss	26
Tax benefit	(8)
Amounts reclassified from accumulated other comprehensive loss, net	18
Net current period other comprehensive (loss) income	(201)
Ending balance	$ (2,828)

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Reclassification from Accumulated Other Comprehensive Income, Current Period, Tax

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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