Summary of Significant Accounting Policies	9 Months Ended
Sep. 27, 2011
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation and Principles of Consolidation The unaudited consolidated financial statements of Panera Bread Company and its subsidiaries (the “Company”) have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”), under the rules and regulations of the United States Securities and Exchange Commission (the “SEC”), and on a basis substantially consistent with the audited consolidated financial statements of the Company as of and for the fiscal year ended December 28, 2010. These unaudited consolidated financial statements should be read in conjunction with such audited consolidated financial statements, which are included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 28, 2010 as filed with the SEC on February 22, 2011. The unaudited consolidated financial statements consist of the accounts of Panera Bread Company and its wholly owned direct and indirect subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. The Consolidated Balance Sheet data as of December 28, 2010 was derived from audited financial statements, but does not include all disclosures required by GAAP. The unaudited consolidated financial statements include all adjustments (consisting of normal recurring adjustments and accruals) that management considers necessary for a fair statement of its financial position and results of operations for the interim periods presented. Interim results are not necessarily indicative of the results for any other interim period or for the entire fiscal year. Recent Accounting Pronouncements On December 30, 2009, the Company adopted the updated guidance issued by the Financial Accounting Standards Board (“FASB”) related to fair value measurements and disclosures, which requires a reporting entity to separately disclose the amounts of significant transfers in and out of Level 1 and Level 2 fair value measurements and to describe the reasons for the transfers. The updated guidance also requires that an entity provide fair value measurement disclosures for each class of assets and liabilities and disclosures about the valuation techniques and inputs used to measure fair value for both recurring and non-recurring Level 2 and Level 3 fair value measurements. This guidance was effective for interim or annual financial reporting periods beginning after December 15, 2009. The adoption of this updated guidance did not have an impact on the Company’s consolidated financial position or results of operations. In addition, the updated guidance requires that in the reconciliation for fair value measurements using significant unobservable inputs, or Level 3 fair value measurements, a reporting entity separately disclose information about purchases, sales, issuances and settlements on a gross basis rather than as one net number. This guidance was effective for interim or annual financial reporting periods beginning after December 15, 2010. The adoption of this updated guidance did not have an impact on the Company’s consolidated financial position or results of operations. In September 2011, the FASB updated its guidance on the annual testing of goodwill for impairment to allow companies to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform the two-step goodwill impairment test required under current accounting standards. The updated guidance is applicable to goodwill impairment tests performed for fiscal years beginning after December 15, 2011, with early adoption permitted. The adoption of this updated guidance is not expected to have a material impact on the Company's consolidated financial position or results of operations.

Summary of Significant Accounting Policies

Basis of Presentation and Principles of Consolidation

The unaudited consolidated financial statements of Panera Bread Company and its subsidiaries (the “Company”) have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”), under the rules and regulations of the United States Securities and Exchange Commission (the “SEC”), and on a basis substantially consistent with the audited consolidated financial statements of the Company as of and for the fiscal year ended December 28, 2010. These unaudited consolidated financial statements should be read in conjunction with such audited consolidated financial statements, which are included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 28, 2010 as filed with the SEC on February 22, 2011. The unaudited consolidated financial statements consist of the accounts of Panera Bread Company and its wholly owned direct and indirect subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. The Consolidated Balance Sheet data as of December 28, 2010 was derived from audited financial statements, but does not include all disclosures required by GAAP.

The unaudited consolidated financial statements include all adjustments (consisting of normal recurring adjustments and accruals) that management considers necessary for a fair statement of its financial position and results of operations for the interim periods presented. Interim results are not necessarily indicative of the results for any other interim period or for the entire fiscal year.

Recent Accounting Pronouncements

On December 30, 2009, the Company adopted the updated guidance issued by the Financial Accounting Standards Board (“FASB”) related to fair value measurements and disclosures, which requires a reporting entity to separately disclose the amounts of significant transfers in and out of Level 1 and Level 2 fair value measurements and to describe the reasons for the transfers. The updated guidance also requires that an entity provide fair value measurement disclosures for each class of assets and liabilities and disclosures about the valuation techniques and inputs used to measure fair value for both recurring and non-recurring Level 2 and Level 3 fair value measurements. This guidance was effective for interim or annual financial reporting periods beginning after December 15, 2009. The adoption of this updated guidance did not have an impact on the Company’s consolidated financial position or results of operations. In addition, the updated guidance requires that in the reconciliation for fair value measurements using significant unobservable inputs, or Level 3 fair value measurements, a reporting entity separately disclose information about purchases, sales, issuances and settlements on a gross basis rather than as one net number. This guidance was effective for interim or annual financial reporting periods beginning after December 15, 2010. The adoption of this updated guidance did not have an impact on the Company’s consolidated financial position or results of operations.

In September 2011, the FASB updated its guidance on the annual testing of goodwill for impairment to allow companies to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform the two-step goodwill impairment test required under current accounting standards. The updated guidance is applicable to goodwill impairment tests performed for fiscal years beginning after December 15, 2011, with early adoption permitted. The adoption of this updated guidance is not expected to have a material impact on the Company's consolidated financial position or results of operations.