Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2024

Financial Instruments

Schedule of available-for-sale securities

	March 31, 2024								December 31, 2023
	Amortized Cost		Gross Unrealized Gain		Gross Unrealized (Loss)		Estimated Fair Value		Amortized Cost		Gross Unrealized Gain		Gross Unrealized (Loss)		Estimated Fair Value
	(in thousands)
Cash, cash equivalents and restricted cash (2)	$	813,817	$	—	$	—	$	813,817	$	642,095	$	—	$	—	$	642,095
U.S. Treasury securities (1)		34,996		—		(531)		34,465		201,522		14		(1,118)		200,418
Municipal securities (1)		36,013		1		(1,358)		34,656		38,091		—		(1,627)		36,464
Total	$	884,826	$	1	$	(1,889)	$	882,938	$	881,708	$	14	$	(2,745)	$	878,977
Classified as:
Cash, cash equivalents and restricted cash (2)								813,817								642,095
Short-term investments								69,121								236,882
Total							$	882,938							$	878,977

(1) Per the Company’s investment policy, all debt securities are classified as short-term investments irrespective of holding period.  

(2) Cash equivalents includes liquid demand deposits, money market funds, and other liquid investments having an original maturity of less than three months.

Schedule of debt securities available-for-sale in unrealized loss position

	Total
	Fair Value		Unrealized Loss
	(in thousands)
U.S. Treasury securities	$	34,465	$	(531)
Municipal securities		31,222		(1,358)
Total	$	65,687	$	(1,889)

Summarized portfolio of available-for-sale securities by contractual maturity

	March 31, 2024
	Amortized Cost		Fair Value
	(in thousands)
Less than or equal to one year	$	52,960	$	52,032
Greater than one year but less than five years		18,049		17,089
Total	$	71,009	$	69,121