Commitments and Contingencies Level 4 (Details) - Environmental Liabilities $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($) sites	Dec. 31, 2017 USD ($)
Accrued Environmental Loss Contingencies, Current	$ 11
Liability	$ 50	$ 52
Number of Sites \| sites	47
Geismar, LA [Member]
Discount rate assumed to record at present value	3.00%
Undiscounted Liability Expected to be Paid	20 years
Geismar, LA Site Contingency, Accrual, Undiscounted Amount	$ 16
Accrual for Environmental Loss Contingencies, Undiscounted, Due Ratably over the Next Five Years	5
Formerly-Owned - Remediation [Member]
Accrued Environmental Loss Contingencies, Current	10
Liability	22	26
Estimated Litigation Liability, Noncurrent	13
Superfund and Offsite Landfills - allocated share: Equal to or Greater than 1% [Member]
Liability	5	6
Superfund and Offsite Landfills - Less than 1% [Member]
Liability	3	2
Geismar, LA [Member]
Liability	13	14
Formerly-Owned - Monitoring Only [Member]
Liability	1	0
Currently-Owned [Member]
Liability	6	$ 4
Minimum [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	41
Minimum [Member] \| Formerly-Owned - Remediation [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	20
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	2
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	1
Minimum [Member] \| Currently-Owned [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	4
Maximum [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	96
Maximum [Member] \| Formerly-Owned - Remediation [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	39
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	6
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	4
Maximum [Member] \| Currently-Owned [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	$ 11

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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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Carrying amount of estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, which is expected to be paid after one year or beyond the normal operating cycle, if longer.

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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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