Goodwill and Acquired Intangible Assets (Amortization Of Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of acquired intangible assets	$ 32,127	$ 26,486	$ 20,303
Cost of license revenue	17,746	18,586	15,819
Amortization of Acquired Intangible Assets Recorded in Cost of Service Revenue	366	0	0
Total amortization expense	$ 50,239	$ 45,072	$ 36,122