Fair Value Measurements Fair Value Measurements (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
US Treasury Securities [Member]
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Unrealized Gain	$ 0	$ 0
Debt Securities, Available-for-Sale, Unrealized Loss	79	1
Debt Securities, Available-for-Sale, Amortized Cost	29,782	5,783
Debt Securities, Available-for-Sale	29,703	5,782
Municipal Bond [Member]
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Unrealized Gain	0	0
Debt Securities, Available-for-Sale, Unrealized Loss	4	8
Debt Securities, Available-for-Sale, Amortized Cost	3,369	26,017
Debt Securities, Available-for-Sale	3,365	26,009
Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Money Market Funds	735,475	579,105
US Government Securities, at Carrying Value	29,703	5,782
Municipal bonds	3,365	26,009
Total	768,543	610,896
Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Money Market Funds	735,475	579,105
US Government Securities, at Carrying Value	29,703	5,782
Municipal bonds	0	0
Total	765,178	584,887
Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Money Market Funds	0	0
US Government Securities, at Carrying Value	0	0
Municipal bonds	3,365	26,009
Total	$ 3,365	$ 26,009

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of unrealized gain on 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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-Publisher FASB
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Amount of unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount 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/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

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-Publisher FASB
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Debt (bills, notes or bonds) that are issued by the government of the United States which are 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. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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