Deferred Revenue And Financing Receivables (Details) (USD $)	6 Months Ended
	Mar. 30, 2013	Mar. 31, 2012	Sep. 30, 2012
Deferred Revenue and Financing Receivables [Line Items]
Maximum payment terms on software purchases for credit-worthy customers (in months)	24 months
Amounts due from customers for contracts with extended payment terms	$ 40,700,000		$ 42,500,000
Receivables past due	700,000		0
Financing receivable	40,740,000		42,463,000
Reserve for credit losses	0
Sale of finance receivable	0	7,500,000
S&P bond rating BBB-1 and above-Tier 1
Deferred Revenue and Financing Receivables [Line Items]
Financing receivable	37,043,000		34,017,000
Internal Credit Assessment-Tier 2
Deferred Revenue and Financing Receivables [Line Items]
Financing receivable	3,697,000		8,446,000
Internal Credit Assessment-Tier 3
Deferred Revenue and Financing Receivables [Line Items]
Financing receivable	0		0
Accounts Receivable
Deferred Revenue and Financing Receivables [Line Items]
Current receivables from contracts	25,700,000		29,500,000
Other Assets
Deferred Revenue and Financing Receivables [Line Items]
Billed but uncollected maintenance receivable	103,300,000		110,700,000
Long-term receivables from contracts	$ 15,000,000		$ 13,000,000