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

No definition available.

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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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- Definition

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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- Definition

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

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- Definition

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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- 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.

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Revenue Recognition (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
Revenue Recognition (Narrative) (Details) - USD ($)	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Contract with customer, liability	$ 58,000,000		$ 58,000,000		$ 56,000,000
Allowance for doubtful accounts receivable, period increase (decrease)	27,000,000	$ 12,000,000
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			85.00%
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			80.00%