Leases (Capital Lease Obligations) (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($)
Operating Leased Assets [Line Items]
Rent expense on non-cancelable leases	$ 179
Rental equipment, net
Operating Leased Assets [Line Items]
Depreciation and amortization	22
Rent expense on short term non-cancelable leases	121
Non-rental depreciation and amortization
Operating Leased Assets [Line Items]
Depreciation and amortization	$ 1

Short Term Rent Expense

No definition available.

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- Definition

The charge for the use of long-lived depreciable capital leased assets for the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 840
-Section 55
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121616545&loc=d3e56872-110439

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121569800&loc=d3e45031-112735

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121573735&loc=d3e41499-112717

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