Debt Senior Notes (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	6 Months Ended		12 Months Ended		24 Months Ended			3 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Nov. 14, 2016	Nov. 14, 2015	Nov. 15, 2018	Dec. 31, 2013	Jun. 30, 2014 2018 Senior Notes [Member]	Jun. 30, 2014 2017 Convertible Senior Notes [Member]	Jun. 30, 2014 2018 Convertible Senior Notes [Member]	Jun. 30, 2014 Face Value [Member] 2018 Senior Notes [Member]	May 08, 2012 Face Value [Member] 2018 Senior Notes [Member]	Nov. 12, 2010 Face Value [Member] 2018 Senior Notes [Member]
Debt Instrument [Line Items]
Convertible senior subordinated notes due 2017	$ 57,500,000					$ 57,500,000		$ 57,500,000
Debt Instrument, Interest Rate, Stated Percentage							8.625%	3.25%	3.00%
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed			102.20%	104.30%	100.00%
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								2.4	2.7
Senior notes	228,269,000					228,070,000				230,000,000	30,000,000	200,000,000
Preferred Stock, Dividend Rate, Percentage	9.75%
Restricted Payments Basket	141,200,000
Convertible senior subordinated notes due 2018	86,250,000					86,250,000			86,250,000
Redemption of preferred shares	0	50,352,000
Dividends, Preferred Stock	$ (2,438,000)