Fair Value Measurements - (Details) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Fair value of the Company's financial assets
Marketable Securities	$ 133,281,000	$ 207,254,000
Assets transferred into level 3	0	0
Assets transferred out of level 3	0	0
Assets transferred from level 1 to level 2	0	0
Assets transferred from level 2 to level 1	0	0
Corporate bonds
Fair value of the Company's financial assets
Marketable Securities	131,706,000	207,254,000
U.S. Government agencies
Fair value of the Company's financial assets
Marketable Securities	1,575,000
Fair Value
Fair value of the Company's financial assets
Total financial assets	140,063,000	209,934,000
Fair Value \| Quoted Prices in Active Markets (Level 1)
Fair value of the Company's financial assets
Total financial assets	6,782,000	2,680,000
Fair Value \| Significant Other Observable Inputs (Level 2)
Fair value of the Company's financial assets
Total financial assets	133,281,000	207,254,000
Money market funds (cash equivalents) \| Fair Value
Fair value of the Company's financial assets
Money market funds (cash equivalents)	6,782,000	2,680,000
Money market funds (cash equivalents) \| Fair Value \| Quoted Prices in Active Markets (Level 1)
Fair value of the Company's financial assets
Money market funds (cash equivalents)	6,782,000	2,680,000
Agency bonds \| Fair Value
Fair value of the Company's financial assets
Marketable Securities	1,575,000
Agency bonds \| Fair Value \| Significant Other Observable Inputs (Level 2)
Fair value of the Company's financial assets
Marketable Securities	1,575,000
Corporate bonds \| Fair Value
Fair value of the Company's financial assets
Marketable Securities	131,706,000	207,254,000
Corporate bonds \| Fair Value \| Significant Other Observable Inputs (Level 2)
Fair value of the Company's financial assets
Marketable Securities	$ 131,706,000	$ 207,254,000

Amounts of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amounts of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
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Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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