SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Equity Securities (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Debt and Equity Securities, FV-NI [Line Items]
Cost	$ 94,275		$ 99,859
Gross Unrealized Gain	57,690	$ 264,879
Gross Unrealized Loss	(25,620)	(2,960)
Fair Value	126,345		361,778
Equity securities - Life Sciences Portfolio (Note 3)
Debt and Equity Securities, FV-NI [Line Items]
Cost	44,854		56,037
Gross Unrealized Gain	57,688	262,811
Gross Unrealized Loss	(463)	(1,488)
Fair Value	102,079		317,360
Equity securities - other common stock
Debt and Equity Securities, FV-NI [Line Items]
Cost	49,421		43,822
Gross Unrealized Gain	2	2,068
Gross Unrealized Loss	(25,157)	$ (1,472)
Fair Value	$ 24,266		$ 44,418

Fair value portion of investments accounted under the equity method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=125513658&loc=d3e32014-111567

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Amount of unrealized gain on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=123583765&loc=SL75117546-209714

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Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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