Business Restructuring (Additional Information) (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended	12 Months Ended				18 Months Ended
	Mar. 31, 2012	Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2014 employees	Jul. 18, 2013
Restructuring and Related Activities [Abstract]
Restructuring Program, Approved Cost								$ 98
Restructuring and Related Cost, Expected Number of Positions Eliminated							1,436
Expected Cash Charges Related to Restructuring			60				93
Restructuring Reserve, Settled with Cash				27
Expected Non-Cash Charges from Restructuring							5
Business restructuring	208	12		98	208	0
Restructuring Reserve, Accrual Adjustment		$ 12
Number of employees impacted				273