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Commitments and Contingencies (Details)
12 Months Ended
Dec. 31, 2019
USD ($)
Employer
Dec. 31, 2018
USD ($)
Guarantor Obligations [Line Items]    
Contributions to plan | $ $ 216,000 $ 227,000
Arrangement Expiring August 31, 2023 | Multiemployer Plan, Plan Information, Available | National Electrical Benefit Fund | Multiemployer Plans, Pension    
Guarantor Obligations [Line Items]    
Number of employers responsible for 5% or more of contributions to multiemployer pension plan | Employer 0  
Percent of employer contribution for multiemployer pension plan (no more than 5%) 5.00%