Accrued Expenses and Other Long-Term Liabilities (Details) - USD ($) $ in Millions		Dec. 31, 2015	Dec. 31, 2014
Accrued Expenses
Defined benefit plan liabilities, current		$ 40	$ 48
Wage and other employee-related liabilities, current		292	294
Environmental liabilities, current		27	26
Accrued interest expense, current		96	88
Asset retirement obligations, current		19	20
Other accrued liabilities, current		80	120
Accrued expenses		554	596
Other Long-Term Liabilities
Defined benefit plan liabilities, noncurrent		719	792
Wage and other employee-related liabilities, noncurrent		100	104
Uncertain income tax position (assets) liabilities, including related penalties and interest	[1]	148	316
Environmental liabilities, noncurrent		231	269
Asset retirement obligations, noncurrent		64	71
Other accrued liabilities, noncurrent		349	387
Other long-term liabilities		1,611	1,939
Uncertain tax position liabilities		391	484
Income Taxes Payable [Member]
Other Long-Term Liabilities
Uncertain tax position liabilities, current		438	$ 168
Deferred Charges and Other Assets, net [Member]
Other Long-Term Liabilities
Uncertain income tax position (assets) liabilities, including related penalties and interest		$ (195)

[1] As of December 31, 2015, our net liability for uncertain tax positions, including related penalties and interest, was $391 million. Of this amount, $438 million was classified as a current liability and reflected in income taxes payable, and $148 million was classified as a long-term liability and reflected in other long-term liabilities as detailed in this table. These liabilities were reduced by a $195 million receivable classified as a long-term asset and reflected in “deferred charges and other assets, net.” As of December 31, 2014, our total liability for uncertain tax positions, including related penalties and interest, was $484 million, with $168 million classified as a current liability and reflected in income taxes payable and the remaining $316 million classified as a long-term liability and reflected in other long-term liabilities as detailed in this table.