Earnings Per Share - Narrative (Details) (USD $) In Thousands, except Share data, unless otherwise specified			3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended
	Mar. 31, 2014	Sep. 30, 2013	Mar. 31, 2014 Stock Options [Member]	Mar. 31, 2014 Common Stock	Mar. 31, 2014 Nonvested Stock Awards [Member]	Mar. 31, 2014 TEU Senior Amortizing Notes	Mar. 31, 2014 Tangible Equity Units	Mar. 31, 2014 Tangible Equity Units	Mar. 31, 2014 Debt Instrument, Convertible, Stock Price Trigger, Range One [Member] TEU Senior Amortizing Notes	Mar. 31, 2014 Debt Instrument, Convertible, Stock Price Trigger, Range Two [Member] TEU Senior Amortizing Notes	Mar. 31, 2014 Debt Instrument, Convertible, Stock Price Trigger, Range Two [Member] Tangible Equity Units	Mar. 31, 2014 Senior Notes [Member] TEU Senior Amortizing Notes	Sep. 30, 2013 Senior Notes [Member] TEU Senior Amortizing Notes	Jul. 17, 2012 Senior Notes [Member] Tangible Equity Units
Earnings Per Share [Line Items]
Stock Issued During Period, Shares, Conversion of Convertible Securities			700,000		300,000		5,200,000
Stock Issued During Period, Shares, Conversion of Units				1,368,108
Debt Instrument, Convertible, Conversion Ratio						1.5372			1.72414	1.40746
Common Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Tangible Equity Units TEUs Converted during period units								890,000	115,433		1,252,675
Debt Instrument, Interest Rate, Stated Percentage														7.50%
Debt Instrument, Convertible, Stock Price Trigger									$ 14.50	$ 17.75
Tangible Equity Units outstanding							3,700,000	3,700,000
Senior notes												$ 9,908	$ 16,141
Shares of common stock issuable upon conversion							5,200,000