XML 62 R45.htm IDEA: XBRL DOCUMENT v3.4.0.3
Impairment fair value, ceiling test and transaction costs (Details 2) - Discontinued operations, held-for-sale or disposed of by sale [Member] - USD ($)
 3 Months Ended 9 Months Ended 12 Months Ended
Mar. 31, 2016
Dec. 31, 2015
Mar. 31, 2015
Mar. 31, 2016
Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]          
Fair value impairment $ (1,400,000)       $ 754,500,000
Fair value impairment after tax (900,000)       475,400,000
Accrued liability of estimated transaction costs 300,000     $ 300,000  
Disposal group transactions costs         $ 2,500,000
Expensed exit and disposal costs 1,800,000     6,700,000  
Estimated exit and disposal costs 4,300,000     4,300,000  
Future lease payment 3,700,000     $ 3,700,000  
Loss on contract termination $ 500,000 $ 3,300,000      
Impairment of oil and gas properties     $ 500,400,000    
Impairment of oil and gas properties, after tax     $ 315,300,000