Derivative Financial Instruments - Fair Value of Cash Flow Hedge Derivative Contracts Included in the Consolidated Balance Sheets (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Sep. 30, 2013
Derivatives, Fair Value
Asset Derivatives	$ 191	$ 0
Liability Derivatives	2,193	1,586
Designated as Hedging Instrument | Cash Flow Hedging
Derivatives, Fair Value
Asset Derivatives	191	0
Liability Derivatives	2,193	1,586
Designated as Hedging Instrument | Cash Flow Hedging | Interest rate swaps | Prepaid expenses and deferred costs
Derivatives, Fair Value
Asset Derivatives	0	0
Designated as Hedging Instrument | Cash Flow Hedging | Interest rate swaps | Deferred costs and other assets
Derivatives, Fair Value
Asset Derivatives	191	0
Designated as Hedging Instrument | Cash Flow Hedging | Interest rate swaps | Accrued liabilities
Derivatives, Fair Value
Liability Derivatives	1,303	1,586
Designated as Hedging Instrument | Cash Flow Hedging | Interest rate swaps | Other long-term liabilities
Derivatives, Fair Value
Liability Derivatives	0	0
Designated as Hedging Instrument | Cash Flow Hedging | Foreign exchange forward currency contracts | Prepaid expenses and deferred costs
Derivatives, Fair Value
Asset Derivatives	0	0
Designated as Hedging Instrument | Cash Flow Hedging | Foreign exchange forward currency contracts | Deferred costs and other assets
Derivatives, Fair Value
Asset Derivatives	0	0
Designated as Hedging Instrument | Cash Flow Hedging | Foreign exchange forward currency contracts | Accrued liabilities
Derivatives, Fair Value
Liability Derivatives	453	0
Designated as Hedging Instrument | Cash Flow Hedging | Foreign exchange forward currency contracts | Other long-term liabilities
Derivatives, Fair Value
Liability Derivatives	$ 437	$ 0