Accounts Receivable and Unbilled Services

6 Months Ended

Jun. 30, 2016

Receivables [Abstract]

Accounts Receivable and Unbilled Services

4. Accounts Receivable and Unbilled Services

Accounts receivable and unbilled services consist of the following (in thousands):

	June 30, 2016			December 31, 2015
Trade:
Billed	$	624,585		$	553,652
Unbilled services		645,460			614,381
		1,270,045			1,168,033
Allowance for doubtful accounts		(12,618	)		(2,284	)
	$	1,257,427		$	1,165,749