Accounts Receivable (Tables)

3 Months Ended

Mar. 31, 2017

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, 2017 and December 31, 2016 (in thousands):

	March 31, 2017			December 31, 2016
Trade accounts receivable	$	278,463		$	260,976
Unbilled accounts receivable	123,463			113,765
Gross accounts receivable	401,926			374,741
Allowance for doubtful accounts	(787		)	(829		)
Reserve for cash-basis customers	(347		)	(5,316		)
Total accounts receivable reserves	(1,134		)	(6,145		)
Accounts receivable, net	$	400,792		$	368,596