Acquisitions (Intangibles - BakerCorp Acquisition) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Jul. 31, 2018	Dec. 31, 2019
BakerCorp
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value	$ 171
BakerCorp \| Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value	$ 166
Life (years)	8 years
BakerCorp \| Trade names and associated trademarks
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value	$ 5
Life (years)	5 years
Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Average original equipment cost, percent		17.70%

Business Combination, Increase in Average Original Equipment Cost, Percent

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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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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=116868840&loc=d3e2207-128464

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472

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