SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS Valuation and Qualifying Accounts (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Movement in Valuation Allowances and Reserves [Roll Forward]
Increase in allowance for doubtful accounts			$ 3
Allowance for doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	18	18	13
Additions Charged to Costs & Expenses	3	1	2
Charged to Other Accounts	0	0	3
Deductions	2	1	0
Balance at End of Period	19	18	18
Deferred tax valuation allowance
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	13	9	0
Additions Charged to Costs & Expenses	7	4	9
Charged to Other Accounts	0	0	0
Deductions	0	0	0
Balance at End of Period	$ 20	$ 13	$ 9

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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