Commitments and Contingencies (Details) - Environmental Liabilities - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Accrued Environmental Loss Contingencies, Current	$ 11	$ 11
Liability	50	50
Estimated Litigation Liability, Current	0	2
Estimated Litigation Liability, Noncurrent		1
Estimated Litigation Liability	2	2
Geismar, LA
Accrual for Environmental Loss Contingencies	$ 13	13
Discount rate assumed to record at present value	3.00%
Undiscounted Liability Expected to be Paid	next 20 years
Accrual for Environmental Loss Contingencies, Gross	$ 16
Accrual for Environmental Loss Contingencies, Undiscounted, Due Ratably over the Next Five Years	5
Less than 1%
Accrual for Environmental Loss Contingencies	3	3
Equal to or greater than 1%
Accrual for Environmental Loss Contingencies	6	5
Currently-owned
Accrual for Environmental Loss Contingencies	5	6
Remediation
Accrual for Environmental Loss Contingencies	22	22
Accrued Environmental Loss Contingencies, Current	10
Estimated Litigation Liability, Noncurrent	13
Monitoring only
Accrual for Environmental Loss Contingencies	1	$ 1
Maximum [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	96
Maximum [Member] | Geismar, LA
Liability	22
Maximum [Member] | Less than 1%
Liability	6
Maximum [Member] | Equal to or greater than 1%
Liability	14
Maximum [Member] | Currently-owned
Liability	11
Maximum [Member] | Remediation
Liability	39
Maximum [Member] | Monitoring only
Liability	4
Minimum [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	41
Minimum [Member] | Geismar, LA
Liability	9
Minimum [Member] | Less than 1%
Liability	2
Minimum [Member] | Equal to or greater than 1%
Liability	5
Minimum [Member] | Currently-owned
Liability	4
Minimum [Member] | Remediation
Liability	20
Minimum [Member] | Monitoring only
Liability	$ 1