Amount of increase (decrease) in allowance for credit loss on accounts receivable.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price.

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Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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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.

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No definition available.

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Revenue Recognition (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable, allowance for credit loss, period increase (decrease)	$ 42
Provision for doubtful accounts		$ 45	$ 40
Deferred revenue	55	56
Contract with customer, asset, after allowance for credit loss	0
Contract with customer, liability, revenue recognized	0	0
Contract with customer, performance obligation satisfied in previous period	$ 0	$ 0
Product concentration risk \| Revenues
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk, percentage (less than 1% of total revenues)	85.00%
Customer concentration risk \| Revenues \| Largest customer
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk, percentage (less than 1% of total revenues)	1.00%	1.00%	1.00%
Customer concentration risk \| Accounts receivable
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk, percentage (less than 1% of total revenues)	1.00%	1.00%
Owned Equipment Rentals \| Product concentration risk \| Revenues
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk, percentage (less than 1% of total revenues)	72.00%
Topic 842 \| Product concentration risk \| Total equipment rentals
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk, percentage (less than 1% of total revenues)	78.00%
General rentals \| Product concentration risk \| Revenues
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk, percentage (less than 1% of total revenues)	80.00%
UNITED STATES \| Geographic Concentration Risk \| Revenues
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk, percentage (less than 1% of total revenues)	91.00%