Summary of Significant Accounting Policies (Detail) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other current assets	$ 428	$ 573
Short-term debt	3,025	32
Other Assets	2,304	2,268
Long-term Debt	$ 15,726	15,636
Accounting Standards Update 2015-03 And 2015-15 [Member] \| Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other current assets		1
Short-term debt		1
Other Assets		82
Long-term Debt		$ 82

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section H

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+ References

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Aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet. Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer).

+ References

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+ References

+ Details

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