Investments in Affiliates (Schedule of Equity Securities Without Readily Determinable Fair Value) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of Investments [Line Items]
Carrying Value	$ 171	$ 170
Dividend income	126	113	$ 117
Other equity securities without readily determinable fair value investee [Member]
Schedule of Investments [Line Items]
Carrying Value	0	0
Dividend income	$ 0	$ 0	4
Acetate Tow [Member] \| Kunming Cellulose Fibers Co. Ltd. [Member]
Schedule of Investments [Line Items]
Ownership percentage	30.00%	30.00%
Carrying Value	$ 14	$ 14
Dividend income	$ 11	$ 11	12
Acetate Tow [Member] \| Nantong Cellulose Fibers Co. Ltd. [Member]
Schedule of Investments [Line Items]
Ownership percentage	31.00%	31.00%
Carrying Value	$ 121	$ 121
Dividend income	$ 91	$ 79	87
Acetate Tow [Member] \| Zhuhai Cellulose Fibers Co. Ltd. [Member]
Schedule of Investments [Line Items]
Ownership percentage	30.00%	30.00%
Carrying Value	$ 30	$ 30
Dividend income	$ 24	$ 22	13
Other Activities [Member] \| InfraServ GmbH & Co. Wiesbaden KG [Member]
Schedule of Investments [Line Items]
Ownership percentage	8.00%	8.00%
Carrying Value	$ 6	$ 5
Dividend income	$ 0	$ 1	$ 1

Equity Securities without Readily Determinable Fair Value Ownership Percentage.

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- Definition

Amount of investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714

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- Definition

Amount of dividend income on nonoperating securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(a))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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+ References

No definition available.

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