Amount of increase (decrease) in the allowance for doubtful accounts.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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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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- Definition

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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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.

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Revenue Recognition (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Contract with customer, liability	$ 59		$ 59		$ 56
Allowance for doubtful accounts receivable, period increase (decrease)	33	$ 27
Contract with customer, asset	0		0
Revenue recognized	0	0	0	$ 0
Contract with customer, performance obligation satisfied in previous period	$ 0	$ 0	$ 0	$ 0
Accounts Receivable \| Customer concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk			1.00%		1.00%
Revenues \| Product concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk			86.00%
Revenues \| Largest customer \| Customer concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk			1.00%		1.00%	1.00%	1.00%
Owned equipment rentals \| Revenues \| Product concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk			73.00%
US \| Revenues \| Geographic Concentration Risk
Property, Plant and Equipment [Line Items]
Concentration risk			91.00%
Topic 842 \| Revenues \| Product concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk			78.00%
General rentals \| Revenues \| Product concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk			79.00%