Impairment Of Long-Lived Assets And Other Lease Charges Closed Restaurant Reserve Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Jan. 01, 2017
Restructuring Reserve [Roll Forward]
Balance, beginning of year	$ 1,513	$ 2,088
Payments, net	(862)	(691)
Other adjustments	122	146
Balance, end of year	2,028	1,513
Provisions for closures [Member]
Restructuring Reserve [Roll Forward]
Provisions for restaurant closures	1,174	59
Changes in estimates of accrued costs	1,174	59
Changes in estimates [Member]
Restructuring Reserve [Roll Forward]
Provisions for restaurant closures	81	(89)
Changes in estimates of accrued costs	$ 81	$ (89)