Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2022

Fair Value Disclosures [Abstract]

Information about Financial Assets Measured at Fair Value on Recurring Basis Based on Three-Tier Fair Value Hierarchy

The following tables present information about the Company’s financial assets measured at fair value on a recurring basis, based on the above three-tier fair value hierarchy:

	June 30, 2022
	Total		Level 1		Level 2		Level 3
	(in thousands)
Equity securities, debt securities and cash equivalents:
Investment in private equity securities	$	15,000	$	—	$	—	$	15,000
U.S. government debt securities		357,573		—		357,573		—
Corporate debt securities		257,716		—		257,716		—
U.S. agency debt securities		81,832		—		81,832		—
Municipal bonds		24,060		—		24,060		—
Yankee debt securities		11,801		—		11,801		—
U.S. treasury bills		59,261		59,261		—		—
Money market accounts		44,209		44,209		—		—
Redeemable preferred stock investment		11,981		—		—		11,981
Total equity securities, debt securities and cash equivalents	$	863,433	$	103,470	$	732,982	$	26,981

	December 31, 2021
	Total		Level 1		Level 2		Level 3
	(in thousands)
Equity securities, debt securities and cash equivalents:
Corporate debt securities	$	332,529	$	—	$	332,529	$	—
U.S. government debt securities		198,157		—		198,157		—
Bond funds		98,799		98,799		—		—
U.S. agency debt securities		69,534		—		69,534		—
Exchange traded funds		35,000		35,000		—		—
Municipal bonds		24,480		—		24,480		—
Yankee debt securities		12,153		—		12,153		—
Redeemable preferred stock investment		21,965		—		—		21,965
Money market accounts		77,067		77,067		—		—
Total equity securities, debt securities and cash equivalents	$	869,684	$	210,866	$	636,853	$	21,965