Property And Equipment (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Property And Equipment [Abstract]
Landlord reimbursement of leasehold improvements	$ 2,100		$ 2,100
Depreciation expense	$ 25	$ 24	$ 49	$ 46