Commitments and Contingencies Level 4 (Details) - Environmental Liabilities - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Accrued Environmental Loss Contingencies, Current	$ 13	$ 13
Environmental Institution of Parana IAP [Member]
Liability	$ 16
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	30	33
Superfund and Offsite Landfills - allocated share: Equal to or Greater than 1% [Member]
Liability	6	7
Superfund and Offsite Landfills - Less than 1% [Member]
Liability	2	1
Geismar, LA [Member]
Liability	14	15
Formerly-Owned - Monitoring Only [Member]
Liability	1	0
Currently-Owned [Member]
Liability	4	$ 5
Minimum [Member] \| Formerly-Owned - Remediation [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	27
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] \| Formerly-Owned - Remediation [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	44
Maximum [Member] \| Superfund and Offsite Landfills - allocated share: Equal to or Greater than 1% [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	13
Maximum [Member] \| Superfund and Offsite Landfills - Less than 1% [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	4
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	$ 10

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Undiscounted Liability Expected to be Paid

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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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Best estimate of the loss exposure for reasonably possible environmental contingencies at an individual site for which no accrual has been recorded.

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