XML 67 R53.htm IDEA: XBRL DOCUMENT v3.10.0.1
Revenues - Revenues by Contract Duration (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Apr. 01, 2017
Sep. 30, 2017
Sep. 30, 2018
Dec. 31, 2017
Successor            
Disaggregation of Revenue [Line Items]            
Revenues $ 1,412.6 $ 1,477.2   $ 2,735.5 $ 4,184.7  
Unrealized Loss (Gain) on Price Risk Fair Value Hedging Instruments 26.8 10.8   1.4 36.3  
Loss (Gain) on Price Risk Fair Value Hedge Ineffectiveness 11.6 12.3   20.0 41.1  
Successor | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues 1,116.9 1,152.1   2,177.8 3,409.7  
Successor | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues 292.3 314.4   495.2 733.7  
Successor | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1] 3.4 10.7   62.5 41.3  
Successor | Operating Segments | Powder River Basin Mining            
Disaggregation of Revenue [Line Items]            
Revenues 373.7 420.9   786.3 1,084.5  
Successor | Operating Segments | Powder River Basin Mining | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues 330.2 373.3   700.0 984.4  
Successor | Operating Segments | Powder River Basin Mining | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues 43.5 47.6   82.0 100.0  
Successor | Operating Segments | Powder River Basin Mining | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1] 0.0 0.0   4.3 0.1  
Successor | Operating Segments | Midwestern U.S. Mining            
Disaggregation of Revenue [Line Items]            
Revenues 208.5 207.7   402.6 607.7  
Successor | Operating Segments | Midwestern U.S. Mining | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues 205.3 199.0   386.3 587.0  
Successor | Operating Segments | Midwestern U.S. Mining | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues 3.1 8.5   16.0 20.5  
Successor | Operating Segments | Midwestern U.S. Mining | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1] 0.1 0.2   0.3 0.2  
Successor | Operating Segments | Western U.S. Mining            
Disaggregation of Revenue [Line Items]            
Revenues 156.1 155.7   281.1 439.4  
Successor | Operating Segments | Western U.S. Mining | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues 146.6 144.2   266.9 400.4  
Successor | Operating Segments | Western U.S. Mining | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues 6.0 14.1   15.2 25.9  
Successor | Operating Segments | Western U.S. Mining | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1] 3.5 (2.6)   (1.0) 13.1  
Successor | Operating Segments | Australian Metallurgical Mining            
Disaggregation of Revenue [Line Items]            
Revenues 370.3 415.9   703.7 1,254.0  
Successor | Operating Segments | Australian Metallurgical Mining | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues 199.5 270.9   524.3 852.1  
Successor | Operating Segments | Australian Metallurgical Mining | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues 169.9 143.2   177.6 399.8  
Successor | Operating Segments | Australian Metallurgical Mining | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1] 0.9 1.8   1.8 2.1  
Successor | Operating Segments | Australian Thermal Mining            
Disaggregation of Revenue [Line Items]            
Revenues 305.1 265.8   505.0 773.9  
Successor | Operating Segments | Australian Thermal Mining | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues 235.3 164.7   300.3 585.8  
Successor | Operating Segments | Australian Thermal Mining | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues 69.8 101.0   204.4 187.5  
Successor | Operating Segments | Australian Thermal Mining | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1] 0.0 0.1   0.3 0.6  
Successor | Corporate, Non-Segment | Trading and Brokerage            
Disaggregation of Revenue [Line Items]            
Revenues 22.6 19.4   24.6 52.7  
Successor | Corporate, Non-Segment | Trading and Brokerage | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues 0.0 0.0   0.0 0.0  
Successor | Corporate, Non-Segment | Trading and Brokerage | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues 0.0 0.0   0.0 0.0  
Successor | Corporate, Non-Segment | Trading and Brokerage | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1] 22.6 19.4   24.6 52.7  
Successor | Corporate, Non-Segment | Corporate and Other            
Disaggregation of Revenue [Line Items]            
Revenues [2] (23.7) (8.2)   32.2 (27.5)  
Successor | Corporate, Non-Segment | Corporate and Other | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues [2] 0.0 0.0   0.0 0.0  
Successor | Corporate, Non-Segment | Corporate and Other | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues [2] 0.0 0.0   0.0 0.0  
Successor | Corporate, Non-Segment | Corporate and Other | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1],[2] (23.7) $ (8.2)   $ 32.2 (27.5)  
Predecessor            
Disaggregation of Revenue [Line Items]            
Revenues     $ 1,326.2      
Unrealized Loss (Gain) on Price Risk Fair Value Hedging Instruments     (16.6)      
Loss (Gain) on Price Risk Fair Value Hedge Ineffectiveness     11.1      
Predecessor | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues     1,054.9      
Predecessor | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues     215.2      
Predecessor | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1]     56.1      
Predecessor | Operating Segments | Powder River Basin Mining            
Disaggregation of Revenue [Line Items]            
Revenues     394.3      
Predecessor | Operating Segments | Powder River Basin Mining | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues     357.7      
Predecessor | Operating Segments | Powder River Basin Mining | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues     36.6      
Predecessor | Operating Segments | Powder River Basin Mining | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1]     0.0      
Predecessor | Operating Segments | Midwestern U.S. Mining            
Disaggregation of Revenue [Line Items]            
Revenues     193.2      
Predecessor | Operating Segments | Midwestern U.S. Mining | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues     193.2      
Predecessor | Operating Segments | Midwestern U.S. Mining | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues     0.0      
Predecessor | Operating Segments | Midwestern U.S. Mining | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1]     0.0      
Predecessor | Operating Segments | Western U.S. Mining            
Disaggregation of Revenue [Line Items]            
Revenues     149.7      
Predecessor | Operating Segments | Western U.S. Mining | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues     129.3      
Predecessor | Operating Segments | Western U.S. Mining | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues     4.2      
Predecessor | Operating Segments | Western U.S. Mining | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1]     16.2      
Predecessor | Operating Segments | Australian Metallurgical Mining            
Disaggregation of Revenue [Line Items]            
Revenues     328.9      
Predecessor | Operating Segments | Australian Metallurgical Mining | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues     240.6      
Predecessor | Operating Segments | Australian Metallurgical Mining | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues     84.0      
Predecessor | Operating Segments | Australian Metallurgical Mining | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1]     4.3      
Predecessor | Operating Segments | Australian Thermal Mining            
Disaggregation of Revenue [Line Items]            
Revenues     224.8      
Predecessor | Operating Segments | Australian Thermal Mining | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues     134.1      
Predecessor | Operating Segments | Australian Thermal Mining | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues     90.4      
Predecessor | Operating Segments | Australian Thermal Mining | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1]     0.3      
Predecessor | Corporate, Non-Segment | Trading and Brokerage            
Disaggregation of Revenue [Line Items]            
Revenues     15.0      
Predecessor | Corporate, Non-Segment | Trading and Brokerage | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues     0.0      
Predecessor | Corporate, Non-Segment | Trading and Brokerage | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues     0.0      
Predecessor | Corporate, Non-Segment | Trading and Brokerage | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1]     15.0      
Predecessor | Corporate, Non-Segment | Corporate and Other            
Disaggregation of Revenue [Line Items]            
Revenues [2]     20.3      
Predecessor | Corporate, Non-Segment | Corporate and Other | One year or longer            
Disaggregation of Revenue [Line Items]            
Revenues [2]     0.0      
Predecessor | Corporate, Non-Segment | Corporate and Other | Short-term contracts            
Disaggregation of Revenue [Line Items]            
Revenues [2]     0.0      
Predecessor | Corporate, Non-Segment | Corporate and Other | Other            
Disaggregation of Revenue [Line Items]            
Revenues [1],[2]     $ 20.3      
Coal Trading Positions | Successor            
Disaggregation of Revenue [Line Items]            
Derivative Liability, Fair Value, Gross Liability [3] $ (75.2)       $ (75.2) $ (38.9)
[1] Other includes revenues from arrangements such as customer contract-related payments, royalties related to coal lease agreements, sales agency commissions, farm income and property and facility rentals, for which contract duration is not meaningful.
[2] Corporate and Other revenue includes unrealized gains and losses related to mark-to-market activity from economic hedge activities intended to hedge future coal sales. Such net unrealized losses were $26.8 million and $10.8 million during the three months ended September 30, 2018 and 2017, respectively, and $36.3 million and $1.4 million during the nine months ended September 30, 2018 and the period April 2 through September 30, 2017, respectively. During the period January 1 through April 1, 2017, such net unrealized gains were $16.6 million. When such gains and losses are realized in connection with recognition of the underlying transaction, they are reclassified to realized gains and losses and are then reflected in Trading and Brokerage revenue (realized losses of $11.6 million and $12.3 million during the three months ended September 30, 2018 and 2017, respectively, and $41.1 million, $20.0 million and $11.1 million during the nine months ended September 30, 2018 and the periods April 2 through September 30, 2017 and January 1 through April 1, 2017, respectively). At September 30, 2018 and December 31, 2017, the financial contracts’ fair values resulted in net liabilities, excluding margin, of $75.2 million and $38.9 million, respectively.
[3] Amounts include net liabilities of $75.2 million and $38.9 million at September 30, 2018 and December 31, 2017, respectively, representing the fair value of financial contracts used to hedge future coal sales, as further described in Note 3. “Revenue Recognition.”