Restaurant Closure Costs and Impairment of Long-Lived Assets (Schedule of Reconciliation of the Impairment Liability) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018 USD ($)
Restaurant Closure Costs and Impairment of Long-Lived Assets [Abstract]
Lease termination costs for closed restaurants, beginning balance	$ 1,416
Charges	8,682
Payments	(2,323)
Lease termination costs for closed restaurants, ending balance	$ 7,775