EQUITY SECURITIES PORTFOLIO INVESTMENT (Tables)

12 Months Ended

Dec. 31, 2022

Investments, Debt and Equity Securities [Abstract]

Unrealized Gain (Loss) on Investments

Equity securities for the periods presented were comprised of the following:

Security Type	Cost		Gross Unrealized Gain		Gross Unrealized Loss		Fair Value
	(In thousands)
December 31, 2022:
Equity securities - Life Sciences Portfolio	$	28,498	$	14,815	$	(617)	$	42,696
Equity securities - other common stock	34,885		4		(15,977)		18,912
Total	$	63,383	$	14,819	$	(16,594)	$	61,608
December 31, 2021:
Equity securities - Life Sciences Portfolio	$	56,037	$	262,811	$	(1,488)	$	317,360
Equity securities - other common stock	43,822		2,068		(1,472)		44,418
Total	$	99,859	$	264,879	$	(2,960)	$	361,778

The following unrealized and realized gains or losses from our investment in the Life Sciences Portfolio are recorded in the change in fair value of equity securities and gain or loss on sale of equity securities, respectively, in the consolidated statements of operations:

	Years Ended December 31,
	2022		2021
	(In thousands)
Change in fair value of equity securities of public    companies	$	(247,126)	$	188,875
Conversion of equity securities without readily    determinable fair value to equity securities of    public companies	—		(102,067)
Gain on sale of equity securities of public    companies	111,717		115,172
Net realized and unrealized (loss) gain	$	(135,409)	$	201,980