Accounts Receivable (Tables)

3 Months Ended

Mar. 31, 2016

Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]

Schedule of Accounts Receivable

Net accounts receivable consisted of the following as of March 31, 2016 and December 31, 2015 (in thousands):

	March 31, 2016			December 31, 2015
Trade accounts receivable	$	267,809		$	262,885
Unbilled accounts receivable	106,674			124,878
Gross accounts receivable	374,483			387,763
Allowance for doubtful accounts	(1,189		)	(906		)
Reserve for cash-basis customers	(8,191		)	(6,458		)
Total accounts receivable reserves	(9,380		)	(7,364		)
Accounts receivable, net	$	365,103		$	380,399