v3.19.3
Revenue from Contract with Customers (Assets and Liabilities) (Details) - USD ($)
$ in Thousands
Sep. 30, 2019
Dec. 31, 2018
Revenue from Contract with Customer [Abstract]    
Billed Contracts Receivable $ 129,017 $ 102,684
Contract with Customer, Asset, after Allowance for Credit Loss 7,685 8,487
Contract with Customer, Liability $ 110,519 $ 122,129