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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Document and Entity Information (USD $)	6 Months Ended
Document and Entity Information (USD $)	Jun. 28, 2011	Aug. 01, 2011 Common Class A [Member]	Jun. 29, 2010 Common Class A [Member]	Aug. 01, 2011 Common Class B [Member]	Jun. 29, 2010 Common Class B [Member]
Entity Registrant Name	PANERA BREAD CO
Entity Central Index Key	0000724606
Document Type	10-Q
Document Period End Date	Jun. 28, 2011
Amendment Flag	false
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-27
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 1,673,643,693		$ 0
Entity Common Stock, Shares Outstanding		29,039,259		1,389,087