Fair Value Measurement

6 Months Ended

Jun. 30, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurement

Note 2 - Fair Value Measurement

The following table summarizes the Company’s investments at June 30, 2024 and December 31, 2023 measured at fair value on a recurring basis (in thousands):

	June 30, 2024							December 31, 2023
			Gross							Gross
			Unrealized			Recorded				Unrealized			Recorded
			(Losses)							(Losses)
	Cost		Gains			Basis		Cost		Gains			Basis
Current:
Cash equivalents:
Money market funds	$	3,334	$	—		$	3,334	$	19,539	$	—		$	19,539
Total cash equivalents		3,334		—			3,334		19,539		—			19,539
Investments:
Corporate bonds		32,258		(3,033	)		29,225		34,472		(3,159	)		31,313
U.S. government agency securities		12,782		(398	)		12,384		12,830		(408	)		12,422
U.S. treasuries		12,454		(1,348	)		11,106		12,448		(1,253	)		11,195
Mortgage-backed securities		12,611		(2,727	)		9,884		13,084		(2,454	)		10,630
Asset backed securities		7,634		(133	)		7,501		13,659		(187	)		13,472
Emerging markets		—		—			—		2,003		(8	)		1,995
Total current investments		77,739		(7,639	)		70,100		88,496		(7,469	)		81,027
Restricted cash and investments (1):
Corporate bonds		82,685		(8,950	)		73,735		82,481		(8,454	)		74,027
U.S. treasuries		54,962		(7,016	)		47,946		109,020		(6,415	)		102,605
Mortgage-backed securities		42,971		(6,080	)		36,891		42,077		(5,216	)		36,861
U.S. government agency securities		16,844		(1,191	)		15,653		16,863		(1,199	)		15,664
Mutual funds		9,999		—			9,999		8,941		—			8,941
Asset backed securities		1,094		(2	)		1,092		799		—			799
Money market funds		247		—			247		337		—			337
Emerging markets		200		—			200		200		2			202
Total restricted cash and    investments		209,002		(23,239	)		185,763		260,718		(21,282	)		239,436
Total investments	$	290,075	$	(30,878	)	$	259,197	$	368,753	$	(28,751	)	$	340,002

(1) Included in restricted cash and investments within the condensed consolidated balance sheets as of June 30, 2024 and December 31, 2023 is restricted cash of $28.7 million and $3.6 million, respectively, which is excluded from the table above. Restricted cash and investments are classified as current and noncurrent on the balance sheet based on the nature of the restriction.

The following table summarizes the Company’s investments at June 30, 2024 and December 31, 2023 measured at fair value on a recurring basis by fair value hierarchy level (in thousands):

	June 30, 2024								December 31, 2023
	Total								Total
	Recorded								Recorded
	Basis		Level 1		Level 2		Other (1)		Basis		Level 1		Level 2		Other (1)
Cash equivalents:
Money market funds	$	3,334	$	—	$	—	$	3,334	$	19,539	$	—	$	—	$	19,539
Investments:
Corporate bonds		29,225		—		29,225		—		31,313		—		31,313		—
U.S. government    agency securities		12,384		—		12,384		—		12,422		—		12,422		—
U.S. treasuries		11,106		—		11,106		—		11,195		—		11,195		—
Mortgage-backed    securities		9,884		—		9,884		—		10,630		—		10,630		—
Asset backed securities		7,501		—		7,501		—		13,472		—		13,472		—
Emerging markets		—		—		—		—		1,995		—		1,995		—
Restricted cash and    investments:
Corporate bonds		73,735		—		73,735		—		74,027		—		74,027		—
U.S. treasuries		47,946		—		47,946		—		102,605		—		102,605		—
Mortgage-backed    securities		36,891		—		36,891		—		36,861		—		36,861		—
U.S. government    agency securities		15,653		—		15,653		—		15,664		—		15,664		—
Mutual funds		9,999		9,999		—		—		8,941		8,941		—		—
Asset backed securities		1,092		—		1,092		—		799		—		799		—
Money market funds		247		—		—		247		337		—		—		337
Emerging markets		200		—		200		—		202		—		202		—
Total investments	$	259,197	$	9,999	$	245,617	$	3,581	$	340,002	$	8,941	$	311,185	$	19,876

(1) Investments in money market funds measured at fair value using the net asset value per share practical expedient are not subject to hierarchy level classification disclosure. The Company invests in money market funds that seek to maintain a stable net asset value. These investments include commingled funds that comprise high-quality short-term securities representing liquid debt and monetary instruments where the redemption value is likely to be the fair value. Redemption is permitted daily without written notice.

The following table summarizes the contractual maturities of the Company’s available-for-sale securities at June 30, 2024 and December 31, 2023. Actual maturities may differ from contractual maturities because borrowers may have the right to prepay obligations with or without prepayment penalties. The table also includes money market funds, which are classified as cash and cash equivalents on the Company’s consolidated balance sheets.

	June 30, 2024
(In thousands)	Less than 1 Year		Between 1 to 5 Years		Between 5 to 10 Years		After 10 Years		Total
Corporate bonds	$	4,319	$	68,730	$	29,744	$	167	$	102,960
U.S. treasuries		1,639		40,945		16,468		—		59,052
U.S. government agency securities		4,949		22,049		1,039		—		28,037
Asset backed securities		—		1,092		6,210		1,291		8,593
Money market funds		3,581		—		—		—		3,581
Emerging markets		—		—		200		—		200
Total	$	14,488	$	132,816	$	53,661	$	1,458	$	202,423
	December 31, 2023
(In thousands)	Less than 1 Year		Between 1 to 5 Years		Between 5 to 10 Years		After 10 Years		Total
U.S. treasuries	$	55,955	$	32,706	$	25,139	$	—	$	113,800
Corporate bonds		6,859		67,731		30,574		176		105,340
U.S. government agency securities		39		27,018		1,029		—		28,086
Money market funds		19,876		—		—		—		19,876
Asset backed securities		—		799		12,182		1,290		14,271
Emerging markets		1,995		—		202		—		2,197
Total	$	84,724	$	128,254	$	69,126	$	1,466	$	283,570

The average contractual maturity of mortgage-backed securities, which are excluded from the table above, was 22 and 23 years as of June 30, 2024 and December 31, 2023, respectively.