Comprehensive Income - Components of Other Comprehensive Income (Loss) and Related Tax Effects (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Amounts Reclassified Out Of Accumulated Other Comprehensive Income Loss [Abstract]
Gain (loss) on asset dispositions and impairments, net	$ (15)	$ 4
Other liabilities		$ 6

The aggregate carrying amount, as of the balance sheet date, of liabilities not separately disclosed in the balance sheet.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Name:	us-gaap_OtherLiabilities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant