Fair Value Measurement (Tables)

3 Months Ended

Mar. 31, 2022

Summary of Investments Measured at Fair Value on Recurring Basis

The following table summarizes the Company’s investments at March 31, 2022 and December 31, 2021 measured at fair value on a recurring basis (in thousands):

	March 31, 2022							December 31, 2021
										Gross
			Gross							Unrealized
			Unrealized			Recorded				Gains			Recorded
	Cost		Losses			Basis		Cost		(Losses)			Basis
Current:
Cash equivalents:
Money market funds	$	29,439	$	—		$	29,439	$	13,384	$	—		$	13,384
Total cash equivalents		29,439		—			29,439		13,384		—			13,384
Investments:
Corporate bonds		41,899		(2,912	)		38,987		41,954		(136	)		41,818
Asset backed securities		19,521		(220	)		19,301		29,533		(38	)		29,495
Mortgage backed securities		17,270		(1,588	)		15,682		18,089		(440	)		17,649
U.S. government agency securities		7,379		(15	)		7,364		7,383		418			7,801
Total current investments		86,069		(4,735	)		81,334		96,959		(196	)		96,763
Restricted cash and investments ⁽¹⁾:
Corporate bonds		107,011		(5,914	)		101,097		117,700		(17	)		117,683
U.S. treasuries		66,525		(4,505	)		62,020		67,614		(342	)		67,272
Mortgage backed securities		58,378		(2,491	)		55,887		64,217		764			64,981
U.S. government agency securities		32,868		(709	)		32,159		32,898		1,281			34,179
Mutual funds		6,992		—			6,992		6,273		—			6,273
Money market funds		427		—			427		528		—			528
Asset backed securities		77		—			77		107		1			108
Total restricted cash and investments		272,278		(13,619	)		258,659		289,337		1,687			291,024
Total investments	$	387,786	$	(18,354	)	$	369,432	$	399,680	$	1,491		$	401,171

(1) Included in restricted cash and investments within the condensed consolidated balance sheets is restricted cash of $8.8 million and $9.2 million as of March 31, 2022 and December 31, 2021, 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.

Summary of Assets Measured at Fair Value on Recurring Basis

The following table summarizes the Company’s investments at March 31, 2022 and December 31, 2021 measured at fair value on a recurring basis by fair value hierarchy level (in thousands):

	March 31, 2022										December 31, 2021
	Total										Total
	Recorded										Recorded
	Basis		Level 1		Level 2		Level 3		Other ⁽¹⁾		Basis		Level 1		Level 2		Level 3		Other ⁽¹⁾
Cash equivalents:
Money market funds	$	29,439	$	—	$	—	$	—	$	29,439	$	13,384	$	—	$	—	$	—	$	13,384
Investments:
Corporate bonds		38,987		—		38,987		—		—		41,818		—		41,818		—		—
Asset backed securities		19,301		—		19,301		—		—		29,495		—		29,495		—		—
Mortgage backed securities		15,682		—		15,682		—		—		17,649		—		17,649		—		—
U.S. government agency securities		7,364		—		7,364		—		—		7,801		—		7,801		—		—
Restricted cash and investments:
Corporate bonds		101,097		—		101,097		—		—		117,683		—		117,683		—		—
U.S. treasuries		62,020		—		62,020		—		—		67,272		—		67,272		—		—
Mortgage backed securities		55,887		—		55,887		—		—		64,981		—		64,981		—		—
U.S. government agency securities		32,159		—		32,159		—		—		34,179		—		34,179		—		—
Mutual funds		6,992		6,992		—		—		—		6,273		6,273		—		—		—
Money market funds		427		—		—		—		427		528		—		—		—		528
Asset backed securities		77		—		77		—		—		108		—		108		—		—
Total investments	$	369,432	$	6,992	$	332,574	$	—	$	29,866	$	401,171	$	6,273	$	380,986	$	—	$	13,912

(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.

Summary of Contractual Maturities of Available for Sale Securities

The following table summarizes the contractual maturities of the Company’s available-for-sale securities at March 31, 2022 and December 31, 2021. Actual maturities may differ from contractual maturities because borrowers may have the right to prepay obligations with or without prepayment penalties.

	March 31, 2022
(In thousands)	Less than 1 Year		Between 1 to 5 Years		Between 5 to 10 Years		After 10 Years		Total
Corporate bonds	$	18,509	$	37,911	$	83,028	$	636	$	140,084
U.S. treasuries		251		3,738		58,031		—		62,020
U.S. government agency securities		—		23,956		15,567		—		39,523
Money market funds		29,680		—		—		—		29,680
Asset backed securities		—		77		2,189		17,112		19,378
Total	$	48,440	$	65,682	$	158,815	$	17,748	$	290,685

	December 31, 2021
(In thousands)	Less than 1 Year		Between 1 to 5 Years		Between 5 to 10 Years		After 10 Years		Total
Corporate bonds	$	24,601	$	35,570	$	99,180	$	150	$	159,501
U.S. treasuries		953		4,295		62,024		—		67,272
U.S. government agency securities		—		25,171		16,809		—		41,980
Asset backed securities		—		108		2,200		27,295		29,603
Money market funds		13,657		—		—		—		13,657
Total	$	39,211	$	65,144	$	180,213	$	27,445	$	312,013