Accounts Receivable (Tables)

6 Months Ended

Jun. 30, 2015

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

Schedule of Accounts Receivable

Net accounts receivable consisted of the following as of June 30, 2015 and December 31, 2014 (in thousands):

	June 30, 2015			December 31, 2014
Trade accounts receivable	$	236,114		$	222,531
Unbilled accounts receivable	118,509			116,070
Gross accounts receivable	354,623			338,601
Allowance for doubtful accounts	(977		)	(1,033		)
Reserve for cash-basis customers	(10,716		)	(7,990		)
Total accounts receivable reserves	(11,693		)	(9,023		)
Accounts receivable, net	$	342,930		$	329,578