XML 39 R29.htm IDEA: XBRL DOCUMENT v3.21.2
Revenue from Contracts with Customers Schedule of Contract Receivables (Details) - USD ($)
$ in Thousands
Jun. 30, 2021
Dec. 31, 2020
Revenue from Contract with Customer [Abstract]    
Billed receivables $ 364,760 $ 312,991
Unbilled receivables 112,002 106,007
Allowance for doubtful accounts (17,918) (18,377)
Receivables—net $ 458,844 $ 400,621