Goodwill and Other Intangible Assets (Other Intangible Assets Associated with Acquisition) (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Net Amount	$ 798	$ 742
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Remaining Amortization Period	29 months	28 months
Net Amount	$ 8	$ 13
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Remaining Amortization Period	9 years	10 years
Net Amount	$ 790	$ 728
NES Rentals Holdings II, Inc. | Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Remaining Amortization Period	1 year
Net Amount	$ 1
NES Rentals Holdings II, Inc. | Customer relationships
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Remaining Amortization Period	10 years
Net Amount	$ 132