XML 72 R59.htm IDEA: XBRL DOCUMENT v3.19.2
Receivables, Net - Summary of Receivables (Details) - USD ($)
$ in Thousands
Jun. 30, 2019
Dec. 31, 2018
Jun. 30, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Accounts receivable-gross $ 552,599 $ 473,757 $ 492,784
Less: allowance for doubtful accounts 641 511 66
Accounts receivable-net 551,958 473,246 492,718
Completed and in Progress [Member]      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Billed 313,185 285,521 340,548
Unbilled 163,950 98,755 71,464
Accounts receivable-gross 477,135 384,276 412,012
Material Sales [Member]      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Accounts receivable-gross 61,204 45,286 64,128
Other Business Products and Services [Member]      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Accounts receivable-gross $ 14,260 $ 44,195 $ 16,644