v3.21.2

REDEMPTION SETTLEMENT ASSETS, RESTRICTED - Narratives (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
REDEMPTION SETTLEMENT ASSETS, RESTRICTED. |  |  |  |
Realized gain (loss) |  | $ 300,000 | $ (600,000) | $ 1,000,000.0
Realized gains or losses | $ 0 | $ 0 | $ 200,000 | $ 0

X
- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563 + Details
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Period Type: | duration

X
- References No definition available. + Details
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Period Type: | duration

X
- Definition Amount of realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI). + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
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Period Type: | duration