Debt (Narrative) (Details) (USD $)	6 Months Ended				6 Months Ended		6 Months Ended		0 Months Ended
	Mar. 31, 2014	Sep. 30, 2013	Mar. 31, 2013	Sep. 30, 2012	Mar. 31, 2014 Minimum [Member]	May 14, 2012 Minimum [Member]	Mar. 31, 2014 Maximum [Member]	May 14, 2012 Maximum [Member]	May 14, 2012 JPMorgan Chase Bank N.A. [Member]
Debt Instrument [Line Items]
Revolving credit facility									$ 450,000,000
Revolving credit facility period									5 years
Available to borrow under the credit facility	402,000,000
Option amount to increase credit facility	250,000,000
Cash on hand	36,362,000	42,850,000	35,880,000	30,215,000
Incremental term loan						25,000,000		250,000,000
Percentage of foreign subsidiaries' share equity	65.00%
Letters of Credit Outstanding, Amount	8,400,000
Line of Credit Facility, Amount Outstanding	$ 40,000,000
Credit facility fees					17.50%		35.00%