Goodwill and Other Intangible Assets (Schedule of Goodwill) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Balance at beginning of year	$ 1,002	$ 1,012
Goodwill Acquired	67
Effects of changes in foreign exchange rates	5	(10)
Balance at end of year	1,074	1,002
Olefins [Member]
Goodwill [Roll Forward]
Balance at beginning of year	30	30
Goodwill Acquired	0
Effects of changes in foreign exchange rates	0	0
Balance at end of year	30	30
Vinyls [Member]
Goodwill [Roll Forward]
Balance at beginning of year	972	982
Goodwill Acquired	67
Effects of changes in foreign exchange rates	5	(10)
Balance at end of year	$ 1,044	$ 972