Document And Entity Information	9 Months Ended
Sep. 30, 2011	Oct. 28, 2011
Document And Entity Information
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2011
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q3
Entity Registrant Name	QUEST SOFTWARE INC
Entity Central Index Key	0001088033
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		83,081,893

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End date of current fiscal year in the format --MM-DD.

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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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