Commitments and Contingencies (Capital Lease Obligations) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Capital Leased Assets [Line Items]
Debt and capital lease obligations	$ 8,162	$ 7,962
Depreciation of rental equipment	976	921	$ 852
Non-rental depreciation and amortization	268	273	246
Less accumulated depreciation and amortization	(16)	(15)
Property and equipment, net	13	18
Rental Equipment
Capital Leased Assets [Line Items]
Depreciation of rental equipment	20	20	22
Property and equipment	186	177
Less accumulated depreciation and amortization	(56)	(45)
Property and equipment, net	130	132
Non-rental Equipment
Capital Leased Assets [Line Items]
Non-rental depreciation and amortization	3	4	$ 5
Non-rental vehicles
Capital Leased Assets [Line Items]
Property and equipment	8	13
Buildings
Capital Leased Assets [Line Items]
Property and equipment	21	20
Subsidiaries
Capital Leased Assets [Line Items]
Debt and capital lease obligations	8,162	7,930
Capital leases \| Subsidiaries
Capital Leased Assets [Line Items]
Debt and capital lease obligations	$ 96	$ 105

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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No definition available.

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The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

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The expense recognized in the current period that allocates the cost of a tangible asset used in providing revenue generating services over the asset's useful life.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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