Fair Value Measurements (Details 1) - Nonrecurring Basis $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)
Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis
Properties, plant and equipment, net (held and used)	$ 490	$ 490
Properties, plant and equipment, net (held for sale)	636	636
Investments and advances	5	5
Total Assets at Fair Value	1,131	1,131
Properties, plant and equipment, net (held and used), Before-Tax Loss	537	618
Properties, plant and equipment, net (held for sale), Before-Tax Loss	203	278
Investments and advances, Before Tax Loss	3	7
Total Assets at Fair Value, Before-Tax Loss	743	903
Level 1
Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis
Properties, plant and equipment, net (held and used)	0	0
Properties, plant and equipment, net (held for sale)	0	0
Investments and advances	0	0
Total Assets at Fair Value	0	0
Level 2
Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis
Properties, plant and equipment, net (held and used)	0	0
Properties, plant and equipment, net (held for sale)	636	636
Investments and advances	2	2
Total Assets at Fair Value	638	638
Level 3
Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis
Properties, plant and equipment, net (held and used)	490	490
Properties, plant and equipment, net (held for sale)	0	0
Investments and advances	3	3
Total Assets at Fair Value	$ 493	$ 493