Commitments and Contingencies Level 4 (Details) - Environmental Liabilities - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Accrued Environmental Loss Contingencies, Current	$ 14	$ 13
Estimated Litigation Liability, Current	3	1
Environmental Institution of Parana IAP [Member]
Liability	17
Geismar, LA [Member]
Accrual for Environmental Loss Contingencies	$ 14	14
Discount rate assumed to record at present value	3.00%
Undiscounted Liability Expected to be Paid	next 22 years
Accrual for Environmental Loss Contingencies, Gross	$ 20
Accrual for Environmental Loss Contingencies, Undiscounted, Due Ratably over the Next Five Years	6
Superfund and Offsite Landfills - allocated share: Less than 1% [Member]
Accrual for Environmental Loss Contingencies	2	2
Superfund and Offsite Landfills - allocated share: Equal to or Greater than 1% [Member]
Accrual for Environmental Loss Contingencies	7	6
Currently-Owned [Member]
Accrual for Environmental Loss Contingencies	4	4
Accrual for Environmental Loss Contingencies, Undiscounted, Due Ratably over the Next Five Years	4
Formerly-Owned - Remediation [Member]
Accrual for Environmental Loss Contingencies	27	30
Accrued Environmental Loss Contingencies, Current		10
Estimated Litigation Liability, Noncurrent	15
Formerly-Owned - Monitoring Only [Member]
Accrual for Environmental Loss Contingencies	0	$ 1
Maximum [Member] \| Geismar, LA [Member]
Liability	22
Maximum [Member] \| Superfund and Offsite Landfills - allocated share: Less than 1% [Member]
Liability	4
Maximum [Member] \| Superfund and Offsite Landfills - allocated share: Equal to or Greater than 1% [Member]
Liability	14
Maximum [Member] \| Currently-Owned [Member]
Liability	9
Maximum [Member] \| Formerly-Owned - Remediation [Member]
Liability	42
Maximum [Member] \| Formerly-Owned - Monitoring Only [Member]
Liability	1
Minimum [Member] \| Geismar, LA [Member]
Liability	9
Minimum [Member] \| Superfund and Offsite Landfills - allocated share: Less than 1% [Member]
Liability	1
Minimum [Member] \| Superfund and Offsite Landfills - allocated share: Equal to or Greater than 1% [Member]
Liability	5
Minimum [Member] \| Currently-Owned [Member]
Liability	3
Minimum [Member] \| Formerly-Owned - Remediation [Member]
Liability	25
Minimum [Member] \| Formerly-Owned - Monitoring Only [Member]
Liability	$ 0

Accrual for Environmental Loss Contingencies, Undiscounted, Due within One to Five Years

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Discount rate assumed to record at present value

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Undiscounted Liability Expected to be Paid

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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-Name Accounting Standards Codification
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Undiscounted amount of the accrual for environmental loss contingencies.

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- Definition

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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- Definition

Carrying amount of reserve for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, which is expected to be paid within one year of the date of the statement of financial position.

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

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