Investments - Equity Securities (Details) $ in Thousands	6 Months Ended
Jun. 30, 2021 USD ($)
Debt and Equity Securities, FV-NI [Line Items]
Cost	$ 119,978
Gross Unrealized Gains	405
Gross Unrealized Losses	(81)
Fair Value	120,302
Fixed income mutual funds
Debt and Equity Securities, FV-NI [Line Items]
Cost	89,962
Gross Unrealized Gains	17
Gross Unrealized Losses	(81)
Fair Value	89,898
Exchange traded mutual funds
Debt and Equity Securities, FV-NI [Line Items]
Cost	30,016
Gross Unrealized Gains	388
Fair Value	$ 30,404

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

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=99377092&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=120269885&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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