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Investment Information - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) lots	Dec. 31, 2021 USD ($) lots
Continuous unrealized loss, qualitative disclosures:
Number of positions in an unrealized loss position (lots) | lots	9,810	4,700
Total number of positions (lots) | lots	12,590	10,240
Largest single loss | $	$ 7,200	$ 1,100
Equity securities, at fair value | $	$ 859,969	$ 1,804,170
Equity Method Investment, Financial Statement, Reported Amounts [Abstract]
Investments, time lag for reporting - low end of range	1 month
Investments, time lag for reporting - high end of range	3 months

X

- Definition

Disclosure regarding factors used to determine that the impairment of securities categorized as available for sale securitie.This item contains disclosure of the largest single loss position in a single lot as of the balance sheet date.

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- Definition

Disclosure regarding factors used to determine that the impairment of securities categorized as available for sale securitie.This item contains disclosure of the number of investment positions held before consideration of those determined to be temporarily impaired.

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- Definition

Equity Method Investments Time Lag For Reporting High End of Range

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- Definition

Equity Method Investments Time Lag For Reporting Low End of Range

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- Definition

Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27290-111563

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922888-210455

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(2))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI https://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740

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