Investments, Debt and Equity Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One	$ 29,472	$ 41,524
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One	29,432	41,343
Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five	1,017
Available-for-sale - matures within one year, Gross unrealized gains	1	1
Available-for-sale - matures within one yearr, Gross unrealized losses	(41)	(182)
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five	1,007
Available-for-sale - matures after one year, Gross unrealized losses	(10)
Available-for-sale - matures after one year, Gross unrealized gains	0
Debt Securities, Available-for-sale	30,439
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(51)
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1
Debt Securities, Available-for-sale, Amortized Cost	30,489
Corporate Bond Securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One	2,265	9,305
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One	2,255	9,239
Available-for-sale - matures within one year, Gross unrealized gains	0	0
Available-for-sale - matures within one yearr, Gross unrealized losses	(10)	(66)
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five	1,007
Available-for-sale - matures after one year, Gross unrealized losses	(10)
Available-for-sale - matures after one year, Gross unrealized gains	0
Municipal Notes
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One	1,045	1,751
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One	1,045	1,747
Available-for-sale - matures within one year, Gross unrealized gains	0	0
Available-for-sale - matures within one yearr, Gross unrealized losses	0	(4)
US Government Agencies Debt Securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One	4,957	2,925
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One	4,942	2,925
Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five	1,017
Available-for-sale - matures within one year, Gross unrealized gains	0	1
Available-for-sale - matures within one yearr, Gross unrealized losses	(15)	(1)
Commercial Paper
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One	8,797	11,237
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One	8,797	11,237
Available-for-sale - matures within one year, Gross unrealized gains	0	0
Available-for-sale - matures within one yearr, Gross unrealized losses	0	0
US Treasury Securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One	12,408	16,306
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One	12,393	16,195
Available-for-sale - matures within one year, Gross unrealized gains	1	0
Available-for-sale - matures within one yearr, Gross unrealized losses	$ (16)	$ (111)

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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