Debt Including Capital Lease Obligations - 7.875% Senior Secured Notes (Details) - USD ($)					2 Months Ended	3 Months Ended			6 Months Ended
	Feb. 06, 2015	Jan. 23, 2015	Jan. 21, 2015	Jan. 31, 2014	Feb. 27, 2015	Jun. 30, 2015	Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014		Feb. 15, 2015	Jan. 07, 2015	Dec. 31, 2014		Feb. 28, 2013	Feb. 05, 2013
Debt Instrument [Line Items]
If redeemed during the 12-month period commencing February 1,									If redeemed during the 12-month period commencing February 1,
Loss on debt extinguishment						$ 0	$ 0		$ (36,212,000)	$ (521,000)
Convertible debt
Debt Instrument [Line Items]
Stated interest rate on debt instrument						4.25%	4.25%		4.25%	4.25%				4.25%
Principal amount of debt component						$ 49,000,000	$ 200,000,000	[1]	$ 49,000,000	$ 200,000,000	[1]	$ 200,000,000		$ 200,000,000	[1]
Redemption price percentage					0.00%
Loss on debt extinguishment					$ 17,000,000
Repurchased convertible notes, principal													$ 151,000,000
7.875% Senior Notes | 7.875% Senior Notes
Debt Instrument [Line Items]
Stated interest rate on debt instrument						7.875%	7.875%		7.875%	7.875%				7.875%		7.875%	7.875%
Principal amount of debt component																$ 425,000,000
Debt discount rate																99.274%
Effective interest rate																8.00%
Redemption price percentage									103.00%
Redemption price									$ (222,000,000)	$ (10,000,000)
7.875% Senior Notes | 7.875% Senior Notes | January 21, 2015 [Member]
Debt Instrument [Line Items]
Redemption price percentage			0.00%
Loss on debt extinguishment			$ 14,000,000
Redemption price			$ 139,000,000
7.875% Senior Notes | 7.875% Senior Notes | January 23, 2015 [Member]
Debt Instrument [Line Items]
Redemption price percentage		0.00%
Loss on debt extinguishment		$ 2,000,000
Redemption price		$ 43,000,000
7.875% Senior Notes | 7.875% Senior Notes | February 6, 2015 [Member]
Debt Instrument [Line Items]
Redemption price percentage	0.00%
Loss on debt extinguishment	$ 2,000,000
Redemption price	$ 43,000,000
7.875% Senior Notes | 7.875% Senior Notes | Debt Instrument, Redemption, Cash Proceeds from Equity Offerings [Member]
Debt Instrument [Line Items]
Redemption price percentage				0.00%					107.90%
Debt instrument, redemption, percentage of principal amount to remain outstanding									100.00%
Loss on debt extinguishment				$ 1,000,000
Redemption price				$ 10,000,000
7.875% Senior Notes | 7.875% Senior Notes | Debt Instrument, Redemption, Cash Proceeds from Equity Offerings [Member] | Maximum
Debt Instrument [Line Items]
Redemption price percentage									0.00%
7.875% Senior Notes | 7.875% Senior Notes | If redeemed during the 12-month period commencing February 1, 2016
Debt Instrument [Line Items]
Redemption price percentage									105.906%
Debt instrument, Maximum Annual Redemption									$ 42,500,000
7.875% Senior Notes | 7.875% Senior Notes | If redeemed during the 12-month period commencing February 1, 2017
Debt Instrument [Line Items]
Redemption price percentage									103.938%
7.875% Senior Notes | 7.875% Senior Notes | If redeemed during the 12-month period commencing February 1, 2018
Debt Instrument [Line Items]
Redemption price percentage									101.969%
7.875% Senior Notes | 7.875% Senior Notes | If redeemed during the 12-month period commencing February 1, 2019
Debt Instrument [Line Items]
Redemption price percentage									100.00%
7.875% Senior Notes | 7.875% Senior Notes | Redemption option upon change of control
Debt Instrument [Line Items]
Redemption price percentage									100.00%

[1] As of December 31, 2014 and June 30, 2014, the Convertible Notes' "if-converted" value did not exceed their principal amount because our common stock price was below the conversion price of the Convertible Notes.