Restructuring Charges and Related Payments and Adjustments (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012
Restructuring Cost and Reserve [Line Items]
Beginning balance	$ 33
Activity during the period:
Charges to restructuring	6
Cash payments	(8)
Ending balance	31
Employee Termination Benefits
Restructuring Cost and Reserve [Line Items]
Beginning balance	30
Activity during the period:
Charges to restructuring	4
Cash payments	(6)
Ending balance	28
Exit Costs
Restructuring Cost and Reserve [Line Items]
Beginning balance	3
Activity during the period:
Charges to restructuring	2
Cash payments	(2)
Ending balance	$ 3