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Fair Value Measurements - Marketable Securities (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)
Changes In Marketable Securities [Roll Forward]
Balance at December 31, 2019	$ 11
Mutual funds purchases	0
Mutual funds sales	(11)
Realized gains (losses)	0
Balance at December 31, 2020	$ 0

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- Definition

Changes In Marketable Securities [Roll Forward]

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- Definition

Marketable Securities, Additions

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- Definition

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- Definition

Amount of investment in marketable security.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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- Definition

Amount of realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI).

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