Casualty, Environmental and Other Reserves - Schedule of Casualty, Environmental and Other Reserves (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Loss Contingencies [Line Items]
Current	$ 118	$ 118
Long-term	267	250
Total	385	368
Total Casualty
Loss Contingencies [Line Items]
Current	44	44
Long-term	137	136
Total	181	180
Personal Injury
Loss Contingencies [Line Items]
Current	37	37
Long-term	84	81
Total	121	118
Occupational
Loss Contingencies [Line Items]
Current	7	7
Long-term	53	55
Total	60	62
Environmental
Loss Contingencies [Line Items]
Current	38	37
Long-term	90	71
Total	128	108
Other
Loss Contingencies [Line Items]
Current	36	37
Long-term	40	43
Total	$ 76	$ 80