Rental Fleet - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Property Subject to or Available for Operating Lease [Line Items]
Rental fleet, net	$ 925,956		$ 989,154
Portable Storage
Property Subject to or Available for Operating Lease [Line Items]
Net orderly liquidation appraisal value of rental fleet	1,100,000
Depreciation expense	$ 23,900	$ 23,100

The net orderly liquidation appraisal value.

No definition available.

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- Definition

The total depreciation charge recorded for property subject to or held for lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

+ Details

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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.

+ Details

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- Definition

The amount of property, by major property class, net of accumulated depreciation, subject to or available for lease as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84164653&loc=d3e41551-112718

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