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Cash Equivalents And Restricted Securities (Tables)

12 Months Ended

Dec. 31, 2020

Cash Equivalents And Restricted Cash And Securities [Abstract]

Summary Of Cash Equivalents And Restricted Securities



				Unrealized			Estimated
				Holding			Market
December 31, 2020	Cost Basis			Gains			Value
Cash equivalents:
Money market funds	$	11,484			--		$	11,484
Restricted securities:
Money market funds		546			--			546
Total assets	$	12,030		$	--		$	12,030

				Unrealized			Estimated
				Holding			Market
December 31, 2019	Cost Basis			Gains			Value
Cash equivalents:
Money market funds	$	1,472			--		$	1,472
Restricted securities:
Money market funds		528			--			528
Total assets	$	2,000		$	--		$	2,000