Commitments and Contingencies Level 4 (Details) - Environmental Liabilities $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($) sites	Dec. 31, 2016 USD ($)
Accrued Environmental Loss Contingencies, Current	$ 11	$ 13
Liability	$ 52	57
Number of Sites \| sites	52
Environmental Institution of Parana IAP [Member]
Liability	$ 13
Geismar, LA [Member]
Discount rate assumed to record at present value	3.00%
Undiscounted Liability Expected to be Paid	21 years
Geismar, LA Site Contingency, Accrual, Undiscounted Amount	$ 18
Accrual for Environmental Loss Contingencies, Undiscounted, Due Ratably over the Next Five Years	6
Currently-Owned [Member]
Accrual for Environmental Loss Contingencies, Undiscounted, Due Ratably over the Next Five Years	4
Formerly-Owned - Remediation [Member]
Liability	26	30
Superfund and Offsite Landfills - allocated share: Equal to or Greater than 1% [Member]
Liability	6	6
Superfund and Offsite Landfills - Less than 1% [Member]
Liability	2	2
Geismar, LA [Member]
Liability	14	14
Formerly-Owned - Monitoring Only [Member]
Liability	0	1
Currently-Owned [Member]
Liability	4	$ 4
Minimum [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	43
Minimum [Member] \| Formerly-Owned - Remediation [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	25
Minimum [Member] \| Superfund and Offsite Landfills - allocated share: Equal to or Greater than 1% [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	5
Minimum [Member] \| Superfund and Offsite Landfills - Less than 1% [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	1
Minimum [Member] \| Geismar, LA [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	9
Minimum [Member] \| Formerly-Owned - Monitoring Only [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	0
Minimum [Member] \| Currently-Owned [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	3
Maximum [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	92
Maximum [Member] \| Formerly-Owned - Remediation [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	42
Maximum [Member] \| Superfund and Offsite Landfills - allocated share: Equal to or Greater than 1% [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	14
Maximum [Member] \| Superfund and Offsite Landfills - Less than 1% [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	5
Maximum [Member] \| Geismar, LA [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	22
Maximum [Member] \| Formerly-Owned - Monitoring Only [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	1
Maximum [Member] \| Currently-Owned [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	$ 8

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Undiscounted amount of the accrual for environmental loss contingencies.

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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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