Debt Obligations - Trade Receivables Securitization Facility (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
Trade Receivables Securitization Facility, Maximum Borrowing Base	$ 200
Trade Receivables Securitization Facility, Collateral At Period End	$ 468	$ 426
Federal Funds Rate [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.50%