Accrued Expenses and Other Current Liabilities (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Summary of Accrued expenses and other current liabilities
Accrued commissions and incentives	$ 240	$ 211
Customer prepayments	86	56
Accrued payroll and related	65	71
Deferred revenue	38	29
Accrued interest expense	32	61
Accrued sponsor monitoring fees	26	32
Income tax payable	26	24
Derivative contracts	8	4
Pension and post-retirement benefit liabilities	2	2
Other	38	47
Accrued expenses and other current liabilities	$ 561	$ 537