Long-term Debt (Details 4) (USD $)	3 Months Ended		9 Months Ended		19 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jan. 31, 2016	Sep. 30, 2013	Mar. 31, 2014 Convertible Senior Subordinated Notes2.50 Percent Due2014 [Member]	Sep. 30, 2013 Convertible Senior Subordinated Notes2.50 Percent Due2014 [Member]
Long-term Debt
Interest expense	$ 12,200,000	$ 11,200,000	$ 34,600,000	$ 33,000,000
Non-cash interest expense	500,000	1,800,000	1,699,000	4,999,000
Weighted average interest rate (as a percent)	7.60%		7.60%			7.70%
Long-term debt
Interest rate on long-term debt (as a percent)							2.50%	2.50%
Amount of debt due to mature during a specified period					$ 0