Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2022

Fair Value Measurements [Abstract]

Schedule of fair value measurement on a recurring basis

December 31, 2022

	Carrying amount in				Fair Value Measurement Using
	balance sheet		Fair Value		Level 1		Level 2		Level 3
Assets:
Cash and cash equivalents:
Commercial paper	$	1,377	$	1,377	$	1,377	$	0	$	0
Treasury Bills		5,974		5,974		5,974		0		0
Treasury Bills - maturity date greater than three months		1,980		1,980		1,980		0		0
Equity securities		56		56		0		0		56

December 31, 2021

	Carrying amount in				Fair Value Measurement Using
	balance sheet		Fair Value		Level 1		Level 2		Level 3
Assets:
Cash and cash equivalents:
Commercial paper	$	1,520	$	1,520	$	1,520	$	0	$	0
Treasury Bills		5,000		5,000		5,000		0		0
Treasury Bills - maturity date greater than three months		3,000		3,000		3,000		0		0
Equity securities		56		56		0		0		56

Summary of changes in level 3 assets at fair value on a recurring basis

	Years Ended December 31,
	2022		2021
Beginning Balance	$	56	$	42
Change in value		0		14
Ending Balance	$	56	$	56