Income Taxes (Schedule Of Deferred Tax Assets And Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Income Tax Expense (Benefit) [Abstract]
Net operating loss carryforwards	$ 23,879	$ 29,785
Foreign tax credits	0	5,403
Capitalized research and development expense	59,562	66,957
Pension benefits	29,651	25,431
Deferred maintenance revenue	34,618	13,786
Stock-based compensation	17,137	15,723
Accrual for litigation	16,310	17,893
Other reserves not currently deductible	18,083	15,728
Amortization of intangible assets	10,658	7,552
Other tax credits	23,899	20,432
Depreciation	5,582	4,816
Other	8,464	6,859
Gross deferred tax assets	247,843	230,365
Valuation allowance	(170,404)	(38,600)
Total deferred tax assets	77,439	191,765
Acquired intangible assets not deductible	(53,030)	(58,303)
Pension prepayments	(12,475)	(10,957)
Other	(651)	(649)
Total deferred tax liabilities	(66,156)	(69,909)
Net deferred tax assets	$ 11,283	$ 121,856