Fair Value Measurements

3 Months Ended

Mar. 31, 2025

Fair Value Measurements [Abstract]

Fair Value Measurements

8.  Fair Value Measurements

The following tables present the major security types we held at March 31, 2025 and December 31, 2024 that we regularly measure and carry at fair value. The following tables segregate each security type by the level within the fair value hierarchy of the valuation techniques we utilized to determine the respective security’s fair value (in thousands):

	At March 31, 2025		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)
Cash equivalents (1)	$	176,876	$	176,876	$	—
Corporate debt securities (2)		988,066		—		988,066
Debt securities issued by U.S. government agencies (3)		182,341		—		182,341
Debt securities issued by the U.S. Treasury (3)		739,136		739,136		—
Debt securities issued by states of the U.S. and political subdivisions of the states (3)		4,670		—		4,670
Other municipal debt (3)		698		—		698
Publicly traded equity securities included in other current assets (4)		3,082		3,082		—
Total	$	2,094,869	$	919,094	$	1,175,775

	At December 31, 2024		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)
Cash equivalents (1)	$	180,445	$	180,445	$	—
Corporate debt securities (3)		1,032,066		—		1,032,066
Debt securities issued by U.S. government agencies (3)		208,998		—		208,998
Debt securities issued by the U.S. Treasury (3)		806,724		806,724		—
Debt securities issued by states of the U.S. and political subdivisions of the states (3)		7,524		—		7,524
Other municipal debt securities (3)		696		—		696
Publicly traded equity securities included in other current assets (4)		5,263		5,263		—
Total	$	2,241,716	$	992,432	$	1,249,284

The following footnotes reference lines in our condensed consolidated balance sheets:

(1) Included in cash and cash equivalents.

(2) $34.0 million was included in cash and cash equivalents, with the difference included in short-term investments.

(3) Included in short-term investments.

(4) Included in other current assets.

Convertible Notes

Our 1.75% Notes and 0% Notes had a fair value of $559.0 million and $623.0 million at March 31, 2025, respectively. Our 1.75% Notes and 0% Notes had a fair value of $569.3 million and $612.8 million at December 31, 2024, respectively. We determine the fair value of our notes based on quoted market prices for these notes, which are Level 2 measurements because the notes do not trade regularly.