Valuation and Qualifying Accounts (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 14	$ 17	$ 20
Charged to Costs and Expenses	1	3	1
Charged to Other Accounts	0	0	0
Deductions	1	6	4
Balance at End of Year	$ 14	$ 14	$ 17