Segment Information (Schedule of Business Segments) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net sales		$ 5,655	$ 6,297	$ 7,155
Other (charges) gains, net		(39)	(203)	9
Operating profit (loss)		664	834	1,334
Equity in net earnings (loss) of affiliates		134	182	233
Depreciation and amortization		350	352	343
Capital expenditures	[1]	348	390	333
Goodwill and intangible assets, net		1,485	1,386
Total assets		10,909	9,476
Increase (decrease) in accrued capital expenditures		(16)	20	(4)
Gain (loss) on sale of investments in affiliates		1,408	0	0
Acetate Tow [Member]
Segment Reporting Information [Line Items]
Net sales		519	636	649
Acetyl Chain [Member]
Segment Reporting Information [Line Items]
Net sales	[2]	3,055	3,275	3,913
Engineered Materials [Member]
Segment Reporting Information [Line Items]
Net sales		2,081	2,386	2,593
Operating Segments [Member] | Acetate Tow [Member]
Segment Reporting Information [Line Items]
Net sales		519	636	649
Other (charges) gains, net		(1)	(88)	(2)
Operating profit (loss)		118	52	130
Equity in net earnings (loss) of affiliates		0	0	0
Depreciation and amortization		36	45	58
Capital expenditures		37	43	29
Goodwill and intangible assets, net		154	153
Total assets		975	977
Gain (loss) on sale of investments in affiliates		0
Operating Segments [Member] | Acetyl Chain [Member]
Segment Reporting Information [Line Items]
Net sales	[3]	3,147	3,392	4,042
Other (charges) gains, net		7	(3)	11
Operating profit (loss)		563	678	1,024
Equity in net earnings (loss) of affiliates		5	4	6
Depreciation and amortization		163	161	148
Capital expenditures		171	208	182
Goodwill and intangible assets, net		301	234
Total assets		3,930	3,489
Gain (loss) on sale of investments in affiliates		0
Operating Segments [Member] | Engineered Materials [Member]
Segment Reporting Information [Line Items]
Net sales		2,081	2,386	2,593
Other (charges) gains, net		(36)	5	0
Operating profit (loss)		235	446	460
Equity in net earnings (loss) of affiliates		115	168	218
Depreciation and amortization		134	131	126
Capital expenditures		106	104	105
Goodwill and intangible assets, net		1,030	999
Total assets		3,990	4,125
Gain (loss) on sale of investments in affiliates		1,408
Corporate, Non-Segment [Member] | Other Activities [Member]
Segment Reporting Information [Line Items]
Net sales		0	0	0
Other (charges) gains, net		(9)	(117)	0
Operating profit (loss)		(252)	(342)	(280)
Equity in net earnings (loss) of affiliates		14	10	9
Depreciation and amortization		17	15	11
Capital expenditures		34	35	17
Goodwill and intangible assets, net		0	0
Total assets		2,014	885
Gain (loss) on sale of investments in affiliates		0
Intersegment [Member]
Segment Reporting Information [Line Items]
Net sales		(92)	(117)	(129)
Other (charges) gains, net		0	0	0
Operating profit (loss)		0	0	0
Equity in net earnings (loss) of affiliates		0	0	0
Depreciation and amortization		0	0	0
Capital expenditures		0	0	0
Goodwill and intangible assets, net		0	0
Total assets		0	0
Gain (loss) on sale of investments in affiliates		0
Intersegment [Member] | Acetyl Chain [Member]
Segment Reporting Information [Line Items]
Net sales		$ 92	$ 117	$ 129

[1] Includes a decrease in accrued capital expenditures of $16 million, an increase in accrued capital expenditures of $20 million and a decrease in accrued capital expenditures of $4 million for the years ended December 31, 2020, 2019 and 2018, respectively.

[2] Excludes intersegment sales of $92 million, $117 million and $129 million for the years ended December 31, 2020, 2019 and 2018 respectively.

[3] Includes intersegment sales of $92 million, $117 million and $129 million for the years ended December 31, 2020, 2019 and 2018, respectively.