ACCOUNTS RECEIVABLE (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Components of accounts receivable under long-term contracts
Total accounts receivable under long-term contracts	$ 227,820	$ 227,433
Less unbilled amounts not currently due	(23,700)	(28,080)
Accounts receivable under long-term contracts, current	204,120	199,353
Period that receivables will not be collected within to be classified as not currently due (in years)	1
U.S. Government Contracts
Components of accounts receivable under long-term contracts
Amounts billed	64,672	50,925
Recoverable costs and accrued profits on progress completed--not billed	50,097	53,569
Total accounts receivable under long-term contracts	114,769	104,494
Commercial Customers
Components of accounts receivable under long-term contracts
Amounts billed	24,384	31,753
Recoverable costs and accrued profits on progress completed--not billed	88,667	91,186
Total accounts receivable under long-term contracts	113,051	122,939
Less unbilled amounts not currently due	$ (23,700)	$ (28,080)