Fair Value Measurements - Schedule of Change in Restricted Investments Valued Using Level 3 Inputs (Details) - Fair Value Recurring Basis $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($)
Fair Value, Assets
Investments, beginning balance	$ 42,609
Other liabilities, ending balance	3,009
Investments, ending balance	32,765
Level 3
Fair Value, Assets
Investments, beginning balance	29,283
Other liabilities, ending balance	3,009
Investments, ending balance	22,639
Other Liabilities \| Level 3
Fair Value, Assets
Other liabilities, beginning balance	0
Value of additional investment received	2,339
Unrealized gain (loss)	670
Other liabilities, ending balance	3,009
Restricted Cash and Investments \| Level 3
Fair Value, Assets
Investments, beginning balance	29,283
Value of additional investment received	4,678
Unrealized gain (loss)	(11,322)
Investments, ending balance	$ 22,639

Other Liabilities Related to Restricted Investments

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- Definition

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

+ 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 (d)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

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

+ References

No definition available.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Cash and investments whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

+ References

No definition available.

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