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Debt (Details Textual) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended			3 Months Ended	1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2012	Apr. 30, 2014	Dec. 31, 2013	Nov. 30, 2013	Aug. 01, 2014	Apr. 12, 2012	Oct. 31, 2013	Mar. 31, 2014
Debt Instrument [Line Items]
Amount of debt outstanding	$ 2,209us-gaap_LongTermDebt	$ 2,355us-gaap_LongTermDebt				$ 2,355us-gaap_LongTermDebt
Debt conversion, aggregate principal amount	75
Percentage ownership of common stock	30.00%
Notes payable to related parties, net of unamortized debt discount	0us-gaap_DueToRelatedPartiesNoncurrent	54us-gaap_DueToRelatedPartiesNoncurrent				54us-gaap_DueToRelatedPartiesNoncurrent
Loss on extinguishment of debt	0	0	41
Current portion of long-term debt	4us-gaap_LongTermDebtCurrent	63us-gaap_LongTermDebtCurrent				63us-gaap_LongTermDebtCurrent
9.75% senior notes due 2014
Debt Instrument [Line Items]
Amount of debt outstanding	0	59				59		59
Stated interest rate	9.75%	9.75%				9.75%
Repurchase amount				123					118
Aggregate consideration				145					136
Loss on extinguishment of debt				41
5.875% senior notes due 2021
Debt Instrument [Line Items]
Amount of debt outstanding	350	350				350				350
Stated interest rate	5.875%	5.875%				5.875%
Percentage of purchase price of notes at their principal amount	101.00%
Percentage of principal amount of the notes being redeemed	100.00%
7.875% senior notes due 2020 (net of discount: 2014 - $1; 2013 - $1)
Debt Instrument [Line Items]
Amount of debt outstanding	249	249				249
Stated interest rate	7.875%	7.875%				7.875%
Percentage of purchase price of notes at their principal amount	101.00%
Percentage of principal amount of the notes being redeemed	100.00%
Unamortized discount	1	1				1
Face amount of notes									250
Defer of financing costs that will be amortized to interest expense									5
8.375% senior notes due 2018
Debt Instrument [Line Items]
Amount of debt outstanding	350	350				350
Stated interest rate	8.375%	8.375%				8.375%
Percentage of purchase price of notes at their principal amount	101.00%
Percentage of principal amount of the notes being redeemed	100.00%
7.75% senior notes due 2018
Debt Instrument [Line Items]
Amount of debt outstanding	500	500				500
Stated interest rate	7.75%	7.75%				7.75%
Percentage of purchase price of notes at their principal amount	101.00%
Percentage of principal amount of the notes being redeemed	100.00%
6.3% senior notes due 2016
Debt Instrument [Line Items]
Amount of debt outstanding	500	500				500
Stated interest rate	6.30%	6.30%				6.30%
Percentage of purchase price of notes at their principal amount	101.00%
Percentage of principal amount of the notes being redeemed	100.00%
10% convertible senior notes due 2018
Debt Instrument [Line Items]
Amount of debt outstanding	0	72				72
Stated interest rate	10.00%	10.00%				10.00%
Debt conversion, aggregate principal amount					75	325
Debt conversion, number of shares issued					6,578,946	28,508,768
Unamortized discount	0	3				3
Aggregate principal amount of outstanding notes		75				75					75
Ship Mortgage Facility
Debt Instrument [Line Items]
Amount of debt outstanding	21	25				25
Current portion of long-term debt	4	4				4
Affiliates of Berkshire Hathaway, Inc. \| 10% convertible senior notes due 2018
Debt Instrument [Line Items]
Notes payable to related parties prior to conversion							300
Notes payable to related parties		56				56
Notes payable to related parties, net of unamortized debt discount		54				54
Related party interest expense	2	29	31
Accrued interest payable to related parties		$ 0.5				$ 0.5
10% convertible senior notes due 2018
Debt Instrument [Line Items]
Percentage of purchase price of notes at their principal amount							105.00%
Maximum \| 7.75% senior notes due 2018
Debt Instrument [Line Items]
Interest rate increase	2.00%