Cash Equivalents And Restricted Cash And Securities (Tables)

12 Months Ended

Dec. 31, 2019

Cash Equivalents And Restricted Cash And Securities [Abstract]

Summary Of Cash Equivalents And Restricted Securities

			Unrealized		Estimated
			Holding		Market
December 31, 2019	Cost Basis		Gains (Losses)		Value
Cash equivalents:
Money market funds	$	1,472		--	$	1,472
Restricted securities:
Money market funds		528		--		528
			Unrealized		Estimated
			Holding		Market
December 31, 2018	Cost Basis		Gains (Losses)		Value
Cash equivalents:
Money market funds	$	1,445		--	$	1,445
Restricted securities:
Money market funds		747		--		747