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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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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.

+ References

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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.

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No definition available.

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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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ENERGY STORAGE SYSTEMS, NET (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Less accumulated depreciation	$ (36,758)
Total energy storage systems, net	119,842		$ 123,703	$ 131,569
Depreciation expense	3,800	$ 3,600
Energy Storage Systems
Property, Plant and Equipment [Line Items]
Total energy storage systems, net			91,593	98,358
Depreciation expense			13,900	9,700
Energy storage systems placed into service
Property, Plant and Equipment [Line Items]
Energy storage systems, gross	145,555		144,425	124,789
Less accumulated depreciation			(33,389)	(20,489)
Energy storage systems not yet placed into service
Property, Plant and Equipment [Line Items]
Energy storage systems, gross	$ 11,045		$ 12,667	$ 27,269