Stockholders' Equity (Schedule of Dividend Increases) (Details) - $ / shares	1 Months Ended
Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2015
Schedule of Dividend Increases [Line Items]
Percent increase in common stock dividend	28.00%	20.00%	20.00%
Common Stock, Dividends, Per Share, Board Increase Announcement, Quarterly	$ 0.46	$ 0.36	$ 0.30
Common stock, Dividends, Per Share, Board Increase Announcement, Annual	$ 1.84	$ 1.44	$ 1.20

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