Investments (Tables)

9 Months Ended

Sep. 30, 2025

Investments, Debt and Equity Securities [Abstract]

The following tables summarize our current investments as of the dates indicated:


	September 30, 2025
	Amortized Cost		Gross Unrealized				Estimated Fair Value
			Gains		Losses

	(In millions)
Corporate debt securities	$	2,574	$	35	$	9	$	2,600
Mortgage-backed securities	996		10		24		982
Asset-backed securities	396		3		3		396
Municipal securities	178		2		2		178
U.S. Treasury notes	22		—		—		22



Other	48		1		1		48
Total	$	4,214	$	51	$	39	$	4,226


	December 31, 2024
	Amortized Cost		Gross Unrealized				Estimated Fair Value
			Gains		Losses

	(In millions)
Corporate debt securities	$	2,769	$	10	$	35	$	2,744
Mortgage-backed securities	953		2		41		914
Asset-backed securities	435		2		6		431
Municipal securities	188		—		5		183
U.S. Treasury notes	5		—		—		5


Other	50		—		2		48
Total	$	4,400	$	14	$	89	$	4,325

Schedule of Contractual Maturities of Investments

The contractual maturities of our current investments as of September 30, 2025 are summarized below:


	Amortized Cost		Estimated Fair Value

	(In millions)
Due in one year or less	$	649	$	646
Due after one year through five years	1,784		1,801
Due after five years through ten years	610		621
Due after ten years	1,171		1,158
Total	$	4,214	$	4,226

Schedule of Available-for-Sale Investments

The following table segregates those available-for-sale investments that have been in a continuous loss position for less than 12 months, and those that have been in a continuous loss position for 12 months or more as of September 30, 2025:


	In a Continuous Loss Position for Less than 12 Months					In a Continuous Loss Position for 12 Months or More
	Estimated Fair Value		Unrealized Losses		Total Number of Positions	Estimated Fair Value		Unrealized Losses		Total Number of Positions

	(Dollars in millions)
Corporate debt securities	$	—	$	—	—	$	493	$	9	243
Mortgage-backed securities	92		1		65	339		23		212
Asset-backed securities	—		—		—	87		3		44
Municipal securities	—		—		—	62		2		67

Other	—		—		—	14		1		17



Total	$	92	$	1	65	$	995	$	38	583


	In a Continuous Loss Position for Less than 12 Months					In a Continuous Loss Position for 12 Months or More
	Estimated Fair Value		Unrealized Losses		Total Number of Positions	Estimated Fair Value		Unrealized Losses		Total Number of Positions

	(Dollars in millions)
Corporate debt securities	$	811	$	10	541	$	935	$	25	449
Mortgage-backed securities	271		5		197	406		36		244
Asset-backed securities	84		1		48	143		5		73
Municipal securities	38		1		27	95		4		89


Other	—		—		—	15		2		16

Total	$	1,204	$	17	813	$	1,594	$	72	871