Investments (Tables)

9 Months Ended

Sep. 30, 2023

Investments

Schedule of gross unrealized gains and losses, and the amortized cost, allowance for credit losses, and fair value of those investments classified as available-for-sale

The amortized cost, gross unrealized gains and losses, fair value of those investments classified as available-for-sale, and allowance for credit losses at September 30, 2023 are summarized as follows (in thousands):

	September 30, 2023
	Amortized		Gross		Gross		Fair		Allowance for
	Cost		Unrealized Gains		Unrealized Losses		Value		Credit Losses
Corporate bonds	$	128,111	$	—	$	—	$	128,111		—
U.S. Treasuries		260,657		—		—		260,657		—
Total	$	388,768	$	—	$	—	$	388,768	$	—

The amortized cost, gross unrealized gains and losses, fair value of those investments classified as available-for-sale, and allowance for credit losses at December 31, 2022 are summarized as follows (in thousands):

	December 31, 2022
	Amortized		Gross		Gross		Fair		Allowance for
	Cost		Unrealized Gains		Unrealized Losses		Value		Credit Losses
Corporate bonds	$	200,735	$	7	$	(7,109)	$	193,633		—
U.S. Treasuries		1,154,879		111		(15,680)		1,139,310		—
Total	$	1,355,614	$	118	$	(22,789)	$	1,332,943	$	—

Schedule of fair value and gross unrealized losses on securities classified as available-for-sale

The Company no longer has available-for-sale securities that are in a loss position as of September 30, 2023.

Schedule of investments classified as equity securities

The cost, gross unrealized gains and losses, and fair value of those investments classified as equity securities at September 30, 2023 are summarized as follows (in thousands):

	September 30, 2023
			Gross		Gross		Fair
	Cost		Unrealized Gains		Unrealized Losses		Value
Fixed income mutual funds	$	70,257	$	—	$	(2,434)	$	67,823
Total	$	70,257	$	—	$	(2,434)	$	67,823

The cost, gross unrealized gains and losses, and fair value of those investments classified as equity securities at December 31, 2022 are summarized as follows (in thousands):

	December 31, 2022
			Gross		Gross		Fair
	Cost		Unrealized Gains		Unrealized Losses		Value
Fixed income mutual funds	$	70,257	$	—	$	(2,620)	$	67,637
Exchange traded mutual funds		75,999		—		(8,800)		67,199
Total	$	146,256	$	—	$	(11,420)	$	134,836

Schedule of the amortized cost and fair value of investments classified as available-for-sale, by contractual maturity

A summary of the amortized cost and fair value of investments classified as available-for-sale, by contractual maturity, as of September 30, 2023 and December 31, 2022 was as follows (in thousands):

	September 30, 2023				December 31, 2022
	Amortized		Fair		Amortized		Fair
Maturity:	Cost		Value		Cost		Value
Less than 12 months	$	281,748	$	281,748	$	1,045,120	$	1,039,333
12 months or greater		107,020		107,020		310,494		293,610
Total	$	388,768	$	388,768	$	1,355,614	$	1,332,943

Summary of investments under the equity method

As of September 30, 2023 and December 31, 2022, the Company accounted for the following investments in the investee’s common stock under the equity method, which are included in the investments in non-consolidated entities and non-marketable equity securities on the interim unaudited condensed consolidated balance sheets (amounts in thousands):

		As of September 30, 2023			As of December 31, 2022
	Formation	Common Stock	Carrying		Common Stock	Carrying
Investee	Date	Ownership %	Value		Ownership %	Value
HyVia	Q2 2021	50%	$	14,876	50%	$	11,281
AccionaPlug S.L.	Q4 2021	50%		3,821	50%		2,225
SK Plug Hyverse	Q1 2022	49%		42,559	49%		8,937
			$	61,256		$	22,443