Income Taxes - Unrecognized Tax Liabilities (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Income Taxes [Abstract]
Unrecognized Tax Benefits Beginning Balance	$ 55,612	$ 54,920
Unrecognized Tax Benefits, Increases Resulting from Current Period Tax Positions	468	747
Unrecognized Tax Benefits, Increases Resulting from Prior Period Tax Positions	2	8
Unrecognized Tax Benefits, Reductions Resulting from Lapse of Applicable Statute of Limitations	3	63
Unrecognized Tax Benefits, Decreases Resulting from Settlements with Taxing Authorities	0	0
Unrecognized Tax Benefits Ending Balance	$ 56,079	$ 55,612