Receivables

12 Months Ended

Sep. 30, 2013

Receivables

6. Receivables

Receivables at September 30, 2013 and 2012 consisted of the following:

	September 30,
	2013			2012
	(In thousands)
Billed	$	115,640		$	113,514
Unbilled (1)		31,250			32,487
		146,890			146,001
Less: allowance for doubtful accounts		(3,157	)		(3,406	)
Receivables, net	$	143,733		$	142,595

(1) Represents revenue recorded in excess of amounts billable pursuant to contract provisions and generally become billable at contractually specified dates or upon the attainment of milestones. Unbilled amounts are expected to be realized within one year.

Activity in the allowance for doubtful accounts was as follows:

	Year Ended September 30,
	2013			2012
	(In thousands)
Balance, beginning of year	$	3,406		$	3,714
Add: expense		327			(122	)
Less: write-offs (net of recoveries)		(576	)		(186	)
Balance, end of year	$	3,157		$	3,406