Property and Equipment (Details) - EOS ENERGY STORAGE, LLC [Member] - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2020	Dec. 31, 2019	Dec. 31, 2018
Total	$ 10,736,000	$ 9,118,000	$ 13,936,000
Less: Accumulated Depreciation and Amortization	(4,919,000)	(3,802,000)	(7,394,000)
Property and equipment, net	5,817,000	5,316,000	6,542,000
Equipment [Member]
Total	$ 7,039,000	$ 5,910,000	9,438,000
Equipment [Member] \| Minimum [Member]
Useful lives	5 years	5 years
Equipment [Member] \| Maximum [Member]
Useful lives	10 years	10 years
Capital lease [Member]
Total	$ 201,000	$ 201,000	225,000
Useful lives	5 years	5 years
Furniture [Member]
Total	$ 176,000	$ 125,000	186,000
Furniture [Member] \| Minimum [Member]
Useful lives	5 years	5 years
Furniture [Member] \| Maximum [Member]
Useful lives	10 years	10 years
Leasehold Improvements [Member]
Total	$ 2,732,000	$ 2,732,000	3,130,000
Useful lives, property and equipment	Lesser of useful life/remaining lease	Lesser of useful life/remaining lease
Tooling [Member]
Total	$ 588,000	$ 150,000	907,000
Tooling [Member] \| Minimum [Member]
Useful lives	2 years	2 years
Tooling [Member] \| Maximum [Member]
Useful lives	3 years	3 years
Construction in progress [Member]
Total			$ 50,000

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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Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).

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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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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