Earnings Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 26, 2012	Jun. 28, 2011	Jun. 26, 2012	Jun. 28, 2011
Amounts used for basic and diluted per share calculations
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 44,137	$ 35,710	$ 85,321	$ 68,484
Weighted average number of shares outstanding - basic (in shares)	29,201	29,867	29,192	29,848
Effect of dilutive stock-based employee compensation awards (in shares)	265	331	272	325
Weighted average number of shares outstanding - diluted (in shares)	29,466	30,198	29,464	30,173
Earnings per common share attributable to Panera Bread Company:
Basic (in dollars per share)	$ 1.51	$ 1.20	$ 2.92	$ 2.29
Diluted (in dollars per share)	$ 1.50	$ 1.18	$ 2.90	$ 2.27

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References+ Details

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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