Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2018

Financial Instruments [Abstract]

Summary Of Financial Instruments Measured At Fair Value

March 31, 2018	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	373	$	--	$	--	$	373
Restricted securities:
Money market funds		808		--		--		808
Total assets	$	1,181	$	--	$	--	$	1,181

December 31, 2017	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	372	$	--	$	--	$	372
Restricted securities:
Money market funds		776		--		--		776
Total assets	$	1,148	$	--	$	--	$	1,148