Stockholders' Equity (Schedule of Dividend Increases) (Details) - $ / shares	1 Months Ended
Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2016
Stockholders' Equity Note [Abstract]
Percent increase in common stock dividend	17.00%	28.00%	20.00%
Quarterly Common Stock Cash Dividend	$ 0.54	$ 0.46	$ 0.36
Annual Common Stock Cash Dividend	$ 2.16	$ 1.84	$ 1.44

Annualized amount of new quarterly dividend payment per share as approved by the board of directors.

No definition available.

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Namespace Prefix:	ce_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration