Specialty Rental Assets, Net (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Less: accumulated depreciation	$ (268,511)		$ (268,511)		$ (241,716)
Specialty rental assets, net	300,329		300,329		311,487
Depreciation	13,908	$ 12,266	26,348	$ 25,162
Specialty rental assets
Property, Plant and Equipment [Line Items]
Specialty rental assets, gross	563,406		563,406		547,375
Depreciation	13,900	$ 12,300	26,300	$ 25,200
Construction-in-process
Property, Plant and Equipment [Line Items]
Specialty rental assets, gross	$ 5,434		$ 5,434		$ 5,828

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of expense for allocation of cost of tangible asset over its useful life directly used in production of good and rendering of service.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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