Commitments and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Guarantor Obligations [Line Items]
Maximum potential payments	$ 1,115		$ 1,163
Carrying value of recorded liabilities related to guarantee	350		$ 351
Loss Contingency [Abstract]
Loss contingency estimate	600
Warranty [Abstract]
Beginning balance	5,137	$ 5,296
Payments made during the period	(1,074)	(963)
Changes in accrual related to warranties issued during the period	693	629
Changes in accrual related to pre-existing warranties	271	185
Foreign currency translation and other	7	9
Ending balance	5,034	$ 5,156
Guarantees to daily rental companies
Guarantor Obligations [Line Items]
Maximum potential payments	974
Carrying value of recorded liabilities related to guarantee	$ 327

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

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Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

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Amount of increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.

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Amount of increase in the standard and extended product warranty accrual from warranties issued.

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