Other (Charges) Gains, Net (Schedule of Restructuring Reserves) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Restructuring Reserve [Roll Forward]
Reserve as of the end of the period	$ 13
Total	13
Employee Termination Benefits [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	4	$ 3
Additions	24	4
Cash payments	(14)	(3)
Other changes	(1)	0
Exchange rate changes	0	0
Reserve as of the end of the period	13	4
Total	13	4
Plant/Office Closures [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	0	2
Additions	1	0
Cash payments	(1)	(2)
Other changes	0	0
Exchange rate changes	0	0
Reserve as of the end of the period	0	0
Total	0	0
Other [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the end of the period	5
Total	5
Other [Member] \| Employee Termination Benefits [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	0	1
Additions	9	0
Cash payments	(4)	(1)
Other changes	0	0
Exchange rate changes	0	0
Reserve as of the end of the period	5	0
Total	5	0
Other [Member] \| Plant/Office Closures [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	0	0
Additions	0	0
Cash payments	0	0
Other changes	0	0
Exchange rate changes	0	0
Reserve as of the end of the period	0	0
Total	0	0
Engineered Materials [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the end of the period	5
Total	5
Engineered Materials [Member] \| Employee Termination Benefits [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	0	1
Additions	10	0
Cash payments	(5)	(1)
Other changes	0	0
Exchange rate changes	0	0
Reserve as of the end of the period	5	0
Total	5	0
Engineered Materials [Member] \| Plant/Office Closures [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	0	0
Additions	0	0
Cash payments	0	0
Other changes	0	0
Exchange rate changes	0	0
Reserve as of the end of the period	0	0
Total	0	0
Acetate Tow [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the end of the period	3
Total	3
Acetate Tow [Member] \| Employee Termination Benefits [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	2	0
Additions	4	2
Cash payments	(3)	0
Other changes	0	0
Exchange rate changes	0	0
Reserve as of the end of the period	3	2
Total	3	2
Acetate Tow [Member] \| Plant/Office Closures [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	0	0
Additions	1	0
Cash payments	(1)	0
Other changes	0	0
Exchange rate changes	0	0
Reserve as of the end of the period	0	0
Total	0	0
Acetyl Chain [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the end of the period	0
Total	0
Acetyl Chain [Member] \| Employee Termination Benefits [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	2	1
Additions	1	2
Cash payments	(2)	(1)
Other changes	(1)	0
Exchange rate changes	0	0
Reserve as of the end of the period	0	2
Total	0	2
Acetyl Chain [Member] \| Plant/Office Closures [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	0	2
Additions	0	0
Cash payments	0	(2)
Other changes	0	0
Exchange rate changes	0	0
Reserve as of the end of the period	0	0
Total	$ 0	$ 0

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of foreign currency translation gain (loss) which decreases (increases) the restructuring reserve.

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