Document and Entity Information	9 Months Ended
Sep. 27, 2011	Oct. 28, 2011 Common Stock Class A [Member]	Oct. 28, 2011 Common Stock Class B [Member]
Entity Registrant Name	Panera Bread Company
Entity Central Index Key	0000724606
Document Type	10-Q
Document Period End Date	Sep. 27, 2011
Amendment Flag	false
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-27
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		28,260,957	1,383,687

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