Impairment Of Long-Lived Assets And Other Lease Charges (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 27, 2015 USD ($)	Sep. 28, 2014 USD ($)	Sep. 27, 2015 USD ($)	Sep. 28, 2014 USD ($)
Restructuring Cost and Reserve [Line Items]
Other lease charges		$ 300	$ 1,500	$ 800
Other Lease Charges, Number of Restaurants		2	10	3
Lease termination charge		$ 100
Impairment Charges			$ 1,200	$ 1,000
Impairment and other lease charges	$ 396	773	2,732	1,822
Previously Impaired [Member]
Restructuring Cost and Reserve [Line Items]
Impairment Charges	$ 400	$ 400	$ 1,000	600
Initial Impairments [Member]
Restructuring Cost and Reserve [Line Items]
Impairment Charges				$ 500
Asset Impairment Charges, Number of Restaurants				5