Accrued Expenses and Other Long-Term Liabilities (Details) - USD ($)		Dec. 31, 2018	Dec. 31, 2017
Accrued Expenses
Defined benefit plan liabilities, current		$ 43,000,000	$ 33,000,000
Wage and other employee-related liabilities, current		302,000,000	278,000,000
Environmental liabilities, current		29,000,000	30,000,000
Environmental credit obligations, current		34,000,000	152,000,000
Accrued interest expense, current		93,000,000	105,000,000
Other accrued liabilities, current		129,000,000	114,000,000
Accrued expenses		630,000,000	712,000,000
Other Long-Term Liabilities
Defined benefit plan liabilities, noncurrent		654,000,000	776,000,000
Wage and other employee-related liabilities, noncurrent		109,000,000	111,000,000
Uncertain tax position liabilities, noncurrent		721,000,000	723,000,000
Repatriation tax liability, noncurrent	[1]	603,000,000	597,000,000
Environmental liabilities, noncurrent		327,000,000	232,000,000
Other accrued liabilities, noncurrent		453,000,000	290,000,000
Other long-term liabilities		2,867,000,000	2,729,000,000
Accrued Expenses and Other Long-Term Liabilities (Textual)
Current portion of repatriation tax liability, included in income taxes payable		$ 0	$ 114,000,000

[1] The current portion of repatriation tax liability is included in income taxes payable. There was no current portion of repatriation tax liability as of December 31, 2018 and $114 million as of December 31, 2017.