XML 52 R39.htm IDEA: XBRL DOCUMENT v3.10.0.1
Casualty, Environmental and Other Reserves - Schedule of Casualty, Environmental and Other Reserves (Details) - USD ($)
$ in Millions
Jun. 30, 2018
Dec. 31, 2017
Loss Contingencies [Line Items]    
Current $ 114 $ 108
Long-term 232 266
Total 346 374
Total Casualty    
Loss Contingencies [Line Items]    
Current 49 49
Long-term 152 179
Total 201 228
Personal Injury    
Loss Contingencies [Line Items]    
Current 42 43
Long-term 105 125
Total 147 168
Occupational    
Loss Contingencies [Line Items]    
Current 7 6
Long-term 47 54
Total 54 60
Environmental    
Loss Contingencies [Line Items]    
Current 37 31
Long-term 54 59
Total 91 90
Other    
Loss Contingencies [Line Items]    
Current 28 28
Long-term 26 28
Total $ 54 $ 56