Cash Equivalents And Restricted Securities (Tables)

3 Months Ended

Mar. 31, 2018

Cash Equivalents And Restricted Securities [Abstract]

Summary Of Cash Equivalents And Restricted Securities

			Unrealized		Estimated
			Holding		Market
March 31, 2018	Cost Basis		Gains		Value
Cash equivalents:
Money market funds	$	373	$	--	$	373
Restricted securities:
Money market funds		808		--		808
			Unrealized		Estimated
			Holding		Market
December 31, 2017	Cost Basis		Gains		Value
Cash equivalents:
Money market funds	$	372	$	--	$	372
Restricted securities:
Money market funds		776		--		776