BACKGROUND AND BASIS OF PRESENTATION (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Mar. 31, 2015
BACKGROUND AND BASIS OF PRESENTATION [Abstract]
Reclassification between prepaid expense and income taxes payable	$ 459

Reclassification between prepaid expense and income taxes payable during the period.

No definition available.

Name:	ccmp_ReclassificationBetweenPrepaidExpenseAndIncomeTaxesPayable
Namespace Prefix:	ccmp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration