Goodwill - Goodwill Activity (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Goodwill [Roll Forward]
Goodwill, beginning of period	$ 1,178,806	$ 1,171,219
Changes to Mobile Mini purchase accounting		8,161
Effects of movements in foreign exchange rates	(1,518)	(574)
Goodwill, end of period	1,177,288	1,178,806
NA Modular
Goodwill [Roll Forward]
Goodwill, beginning of period	521,049	235,828
Changes to Mobile Mini purchase accounting		285,000
Effects of movements in foreign exchange rates	396	221
Goodwill, end of period	521,445	521,049
NA Storage
Goodwill [Roll Forward]
Goodwill, beginning of period	492,552	726,529
Changes to Mobile Mini purchase accounting		(233,666)
Effects of movements in foreign exchange rates	(56)	(311)
Goodwill, end of period	492,496	492,552
UK Storage
Goodwill [Roll Forward]
Goodwill, beginning of period	65,098	65,600
Changes to Mobile Mini purchase accounting		0
Effects of movements in foreign exchange rates	(1,858)	(502)
Goodwill, end of period	63,240	65,098
Tank and Pump
Goodwill [Roll Forward]
Goodwill, beginning of period	100,107	143,262
Changes to Mobile Mini purchase accounting		(43,173)
Effects of movements in foreign exchange rates	0	18
Goodwill, end of period	$ 100,107	$ 100,107

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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