Investments - Equity Securities (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)
Debt and Equity Securities, FV-NI [Line Items]
Cost	$ 141,257
Gross Unrealized Gains	7,312
Gross Unrealized Losses	(574)
Fair Value	147,995
Fixed income mutual funds
Debt and Equity Securities, FV-NI [Line Items]
Cost	70,247
Gross Unrealized Losses	(574)
Fair Value	69,673
Exchange traded mutual funds
Debt and Equity Securities, FV-NI [Line Items]
Cost	71,010
Gross Unrealized Gains	7,312
Fair Value	$ 78,322

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740

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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

+ References

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Amount of unrealized gain on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=123583765&loc=SL75117546-209714

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Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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