Goodwill and Acquired Intangible Assets (Amortization Of Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of acquired intangible assets	$ 26,486	$ 20,303	$ 18,319
Cost of license revenue	18,586	15,819	15,393
Total amortization expense	$ 45,072	$ 36,122	$ 33,712