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Retirement and Compensation Plans (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Multiemployer Plans [Line Items]      
Entity Tax Identification Number 42-1411715    
Multiemployer Plan Number 001    
Multiemployer Plan, Contributions by Employer $ 15,000 $ 30,000 $ 45,000