Specialty Rental Assets, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2019
Specialty rental assets
Less: accumulated depreciation	$ (156,955)	$ (200,376)
Specialty rental assets, net	293,559	353,695
Specialty rental assets
Specialty rental assets
Specialty rental assets, gross	432,158	545,399
Construction-in-process
Specialty rental assets
Specialty rental assets, gross	18,356	8,672
Capital lease \| Specialty rental assets
Specialty rental assets
Specialty rental assets, gross	22,800	1,300
Less: accumulated depreciation	(8,200)	$ 0
Gross cost transferred	$ 22,200

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 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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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Amount of increase (decrease) of physical assets used in the normal conduct of business and not intended for resale, from reclassification, impairment, donation, or changes classified as other. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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