Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2016	Jun. 30, 2015	Jun. 28, 2016	Jun. 30, 2015
Amounts used for basic and diluted per share calculations
Net income attributable to Panera Bread Company	$ 34,501	$ 41,929	$ 69,589	$ 73,789
Weighted average number of shares outstanding - basic (in shares)	23,569	26,158	23,838	26,319
Effect of dilutive stock-based employee compensation awards (in shares)	133	117	122	104
Weighted average number of shares outstanding - diluted (in shares)	23,702	26,275	23,960	26,423
Earnings per common share:
Basic (in dollars per share)	$ 1.46	$ 1.60	$ 2.92	$ 2.80
Diluted (in dollars per share)	$ 1.46	$ 1.60	$ 2.90	$ 2.79