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Basis of Presentation and Summary of Significant Accounting Policies - Certain Risks and Concentrations (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2022 | Mar. 31, 2021 | Dec. 31, 2021
Total Expenditures | Supplier concentration risk | Offshore Supplier |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk (less than for geographic concentration risk) | 19.00% | 26.00% |
Accounts Payable | Supplier concentration risk | Offshore Supplier |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk (less than for geographic concentration risk) | 54.00% |  | 60.00%
Distributor To The U.S. Navy | Revenue | Customer concentration risk |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk (less than for geographic concentration risk) | 15.00% | 50.00% |
Shipbuilder For U.S. Navy | Accounts receivable | Customer concentration risk |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk (less than for geographic concentration risk) | 11.00% | 36.00% |
Shipbuilder For U.S. Navy | Revenue | Customer concentration risk |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk (less than for geographic concentration risk) | 21.00% |  |
Commercial Building Systems Provider | Accounts receivable | Customer concentration risk |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk (less than for geographic concentration risk) | 28.00% |  |
Commercial Building Systems Provider | Revenue | Customer concentration risk |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk (less than for geographic concentration risk) | 19.00% |  |
Distributor To The U.S. Navy Combined With Sales To Shipbuilders | Revenue | Customer concentration risk |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk (less than for geographic concentration risk) | 37.00% | 57.00% |
Regional Commercial Lighting Retrofit Company | Revenue | Customer concentration risk |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk (less than for geographic concentration risk) |  | 11.00% |
Distributor To The U.S. Department Of Defense | Accounts receivable | Customer concentration risk |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk (less than for geographic concentration risk) | 10.00% | 20.00% |

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