Debt Senior Notes (Details) (USD $)	3 Months Ended	9 Months Ended				3 Months Ended		3 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 2018 Senior Notes [Member]	Dec. 31, 2012 2018 Senior Notes [Member]	Sep. 30, 2013 2017 Convertible Senior Notes [Member]	Dec. 31, 2012 2017 Convertible Senior Notes [Member]	Sep. 30, 2013 2018 Convertible Senior Notes [Member]	Dec. 31, 2012 2018 Convertible Senior Notes [Member]	Sep. 30, 2013 Face Value [Member] 2018 Senior Notes [Member]
Debt Instrument [Line Items]
Convertible subordinated debt						$ 57,500,000	$ 57,500,000	$ 86,250,000	$ 0
Debt Instrument, Interest Rate, Stated Percentage				8.625%		3.25%		3.00%
Debt Instrument, Convertible, Conversion Ratio						42.0159		30.9478
Debt Instrument Convertible Principal Amount Used In Conversion Rate Calculation						1,000		1,000
Debt Instrument, Convertible, Conversion Price						$ 23.80		$ 32.31
Stock Issued During Period, Shares, Other						2,400,000		2,700,000
Senior notes				227,970,000	227,670,000					230,000,000
Preferred Stock, Dividend Rate, Percentage		9.75%
Restricted Payments Basket	127,500,000	127,500,000
Preferred shares redeemed during period		2,000
Redemption of preferred shares		50,352,000	0
Dividends, Preferred Stock	$ 1,200,000	$ (2,438,000)