
		December 31, 2025								December 31, 2024
(dollars in millions)	Contractual Maturity	Amortized Cost		Unrealized Gain		Unrealized Loss		Fair Value		Amortized Cost		Unrealized Gain		Unrealized Loss		Fair Value
Commercial paper	0 to 1 years	$	22.6	$	—	$	—	$	22.6	$	37.1	$	—	$	—	$	37.1
Corporate debt securities	0 to 1 years	622.6		1.7		—		624.3		527.0		0.6		(0.1)		527.5
Securities of government-sponsored entities	0 to 1 years	120.2		0.3		—		120.5		278.2		0.3		—		278.5
		$	765.4	$	2.0	$	—	$	767.4	$	842.3	$	0.9	$	(0.1)	$	843.1

Corporate debt securities	1 to 3 years	$	945.0	$	4.5	$	(0.5)	$	949.0	$	584.4	$	2.0	$	(1.0)	$	585.4
Securities of government-sponsored entities	1 to 3 years	113.8		0.3		(0.1)		114.0		154.4		0.3		(0.6)		154.1
		$	1,058.8	$	4.8	$	(0.6)	$	1,063.0	$	738.8	$	2.3	$	(1.6)	$	739.5

Unrealized losses on available-for-sale debt securities were primarily due to changes in interest rates. Our investments in available-for-sale debt securities are of high credit quality, and we do not intend to sell these investments and it is not more likely than not that we will be required to sell these investments before their maturity. No allowance for credit losses was recognized as of December 31, 2025 or 2024.

The following table presents available-for-sale debt securities that were in an unrealized loss position as of December 31, 2025, aggregated by major security type and length of time in a continuous loss position.


	Less Than 12 Months				12 Months or Longer				Total
(in millions)	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss

Corporate debt securities	$	298.2	$	(0.5)	$	—	$	—	$	298.2	$	(0.5)

The following table presents available-for-sale debt securities that were in an unrealized loss position as of December 31, 2024, aggregated by major security type and length of time in a continuous loss position.


	Less Than 12 Months				12 Months or Longer				Total
(in millions)	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss

Corporate debt securities	$	334.9	$	(1.1)	$	—	$	—	$	334.9	$	(1.1)
Securities of government-sponsored entities	$	123.8	$	(0.6)	$	—	$	—	$	123.8	$	(0.6)