Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Accounts payable and accrued expenses - related parties	$ 2,517	$ 1,194
Director
Related Party Transaction [Line Items]
Costs incurred with related parties	69	19
Accounts payable and accrued expenses - related parties	0	73
Equity Method Investee \| Holtec International
Related Party Transaction [Line Items]
Accounts payable and accrued expenses - related parties	2,382	$ 1,121
Affiliated Entity \| Consultant Fees
Related Party Transaction [Line Items]
Accounts payable and accrued expenses - related parties	138
Affiliated Entity \| B.Riley Securities, Inc
Related Party Transaction [Line Items]
Due from related parties, current	432
Corporate Joint Venture \| Hi-Power
Related Party Transaction [Line Items]
Due from related parties, current	$ 278

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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- Definition

Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ 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.

+ References

No definition available.

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