Fair Value of Financial Instruments - Rollforward of Balance Sheet Amounts Within Level 3 Valuation Hierarchy (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Available-for-sale Securities
Assets measured on recurring basis, unobservable input reconciliation, calculation [Roll Forward]
Transfers out of Level 3			$ 0
Recurring \| Other investments
Assets measured on recurring basis, unobservable input reconciliation, calculation [Roll Forward]
Fair value, beginning of period	$ 106,694	$ 62,129	100,996	$ 47,759
Total realized gains included in income	6,669	6,957	8,379	10,397
Changes in unrealized gains/losses included in other comprehensive income	0	0	0	0
Purchases	11,352	13,124	18,763	25,556
Issuances	0	0	0	0
Settlements	(3,104)	(3,455)	(6,527)	(4,957)
Transfers out of Level 3	0	0	0	0
Fair value, end of period	121,611	78,755	121,611	78,755
Total realized gains included in income	6,669	6,957	8,379	10,397
Recurring \| Available-for-sale Securities
Assets measured on recurring basis, unobservable input reconciliation, calculation [Roll Forward]
Fair value, beginning of period	662	13,513	828	15,497
Total realized gains included in income	1	1,256	3	1,298
Changes in unrealized gains/losses included in other comprehensive income	(7)	(1,293)	(17)	(3,168)
Purchases	0	0	0	0
Issuances	0	0	0	0
Settlements	0	(12,636)	(158)	(12,787)
Transfers out of Level 3	0	0	0	0
Fair value, end of period	656	840	656	840
Total realized gains included in income	$ 1	$ 1,256	$ 3	$ 1,298

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
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- Definition

Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

+ References

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-Name Accounting Standards Codification
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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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