Debt Senior Notes (Details) (USD $)	3 Months Ended		6 Months Ended		3 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Mar. 31, 2014 8.25% Interest Rate [Member]	Mar. 31, 2014 Senior Notes [Member] 8.25% Interest Rate [Member]	Jun. 30, 2014 Senior Notes [Member] 6.5% Interest Rate [Member]	Jun. 30, 2013 Senior Notes [Member] 6.5% Interest Rate [Member]
Debt Instrument [Line Items]
Principal						$ 150,000,000	$ 300,000,000
Stated interest rate, senior notes						8.25%	6.50%	6.50%
Senior Notes Aggregate Redemption Amount					156,200,000
Loss on early extinguishment of debt	0	0	(7,677,000)	0	7,700,000
Redemption Premium					6,200,000
Debt Instrument, Unamortized Discount					$ 1,500,000