Commitments And Contingencies (Operating Lease Rental Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Operating Leases, Rent Expense, Net [Abstract]
Minimum rentals	$ 15,107	$ 19,505	$ 50,951	$ 60,693
Contingent rentals	4,175	4,264	11,870	12,086
Less: Sublease rentals	(37)	(55)	(110)	(144)
Total rent expense	19,245	23,714	62,711	72,635
Common area maintenance, parking and storage.	$ 2,300	$ 2,500	$ 7,100	$ 7,700