ACCOUNTS RECEIVABLE (Tables)

6 Months Ended

12 Months Ended

Mar. 31, 2013

Sep. 30, 2012

ACCOUNTS RECEIVABLE

Schedule of components of accounts receivable under long-term contracts

The components of accounts receivable are as follows (in thousands):

	March 31,			September 30,
	2013			2012
Trade and other receivables	$	21,060		$	17,543
Long-term contracts:
Billed	108,774			91,132
Unbilled	305,713			264,555
Allowance for doubtful accounts	(651		)	(463		)
Total accounts receivable	434,896			372,767
Less estimated amounts not currently due	(20,830		)	(22,070		)
Current accounts receivable	$	414,066		$	350,697

The components of accounts receivable under long-term contracts are as follows (in thousands):

	September 30,
	2012			2011			2010			2009
				(As restated)			(As restated)			(As restated)
U.S. government contracts:
Amounts billed	$	48,387		$	64,672		$	50,925		$	62,093
Recoverable costs and accrued profits on progress completed—not billed		95,764			50,748			54,403			43,022
		144,151			115,420			105,328			105,115
Commercial customers:
Amounts billed		42,745			24,384			31,753			41,907
Recoverable costs and accrued profits on progress completed—not billed		168,791			91,322			92,897			89,087
		211,536			115,706			124,650			130,994
		355,687			231,126			229,978			236,109
Less unbilled amounts not currently due—commercial customers		(22,070	)		(23,700	)		(28,080	)		(13,400	)
	$	333,617		$	207,426		$	201,898		$	222,709