v2.3.0.11

Document and Entity Information	6 Months Ended
Document and Entity Information	Jun. 30, 2011	Jul. 27, 2011
Document and Entity Information
Entity Registrant Name	CEPHALON INC
Entity Central Index Key	0000873364
Document Type	10-Q
Document Period End Date	Jun. 30, 2011
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		77,938,118
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q2

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This is focus fiscal year of the document report in CCYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006.

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The type of document being provided (such as 10-K, 10-Q, N-1A, etc). The document type is limited to the same value as the supporting SEC submission type, minus any "/A" suffix. The acceptable values are as follows: S-1, S-3, S-4, S-11, F-1, F-3, F-4, F-9, F-10, 6-K, 8-K, 10, 10-K, 10-Q, 20-F, 40-F, N-1A, 485BPOS, 497, NCSR, N-CSR, N-CSRS, N-Q, 10-KT, 10-QT, 20-FT, and Other.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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CEPHALON INC 10-Q