Accounts Receivable (Tables)

6 Months Ended

Jun. 30, 2012

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

Schedule of Accounts Receivable

Net accounts receivable consisted of the following (in thousands):

	June 30, 2012			December 31, 2011
Trade accounts receivable	$	143,804		$	142,166
Unbilled accounts	67,903			73,325
Gross accounts receivable	211,707			215,491
Allowance for doubtful accounts	(1,706		)	(1,627		)
Reserve for cash-basis customers	(3,685		)	(2,928		)
Total accounts receivable reserves	(5,391		)	(4,555		)
Accounts receivable, net	$	206,316		$	210,936