Chapter 11 Bankruptcy Proceedings Combined Balance Sheet (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Cash and Cash Equivalents, at Carrying Value $ 573,600 $ 1,730,335 $ 1,364,953 $ 2,282,155
Short-term intercompany receivables 0 0    
Other Assets, Current 74,293 40,461    
Total current assets 1,713,412 3,748,186    
Property, plant and equipment, net 2,432,933 3,337,545    
Long-term intercompany receivables 0 0    
Other assets 456,355 477,306    
Total assets 5,430,591 8,679,954    
Accounts payable 279,804 346,128    
Other Accrued Liabilities, Current 230,165 244,610    
Total current liabilities 1,709,380 2,286,590    
Total liabilities 2,801,862      
External Liabilities Subject To Compromise 4,593,493      
Intercompany Liabilities Subject To Compromise 0      
Total liabilities 2,801,862 8,324,567    
Stockholders' Equity Attributable to Parent (1,964,764) 355,387    
Total liabilities and stockholders' equity 5,430,591 8,679,954    
Chapter 11 Entities [Member]        
Cash and Cash Equivalents, at Carrying Value 321,690 1,133,276    
Short-term intercompany receivables 127,215      
Other Assets, Current 16,584      
Total current assets 465,489      
Property, plant and equipment, net 48,167      
Intangible Assets, Net (Including Goodwill) 18,000      
Investments In And Advances To Non-Debtor Subsidiaries 423,163      
Long-term intercompany receivables 1,712,199      
Other assets 1,339      
Total assets 2,668,357      
Accounts payable 1,996      
Other Accrued Liabilities, Current 20,257      
Total current liabilities 22,253      
Liabilities, Noncurrent 4,805      
Total liabilities 27,058      
External Liabilities Subject To Compromise 4,593,493      
Intercompany Liabilities Subject To Compromise 12,570      
Total liabilities 4,633,121      
Stockholders' Equity Attributable to Parent (1,964,764)      
Total liabilities and stockholders' equity $ 2,668,357