Investments (Tables)

9 Months Ended

Sep. 30, 2022

Investments, Debt and Equity Securities [Abstract]

Schedule of Investments

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

	September 30, 2022
	Amortized Cost		Gross Unrealized				Estimated Fair Value
			Gains		Losses
	(In millions)
Corporate debt securities	$	2,431	$	—	$	148	$	2,283
Mortgage-backed securities	804		—		61		743
Asset-backed securities	322		—		19		303
Municipal securities	159		—		11		148
U.S. Treasury notes	117		—		1		116
Other	49		—		3		46
Total	$	3,882	$	—	$	243	$	3,639

	December 31, 2021
	Amortized Cost		Gross Unrealized				Estimated Fair Value
			Gains		Losses
	(In millions)
Corporate debt securities	$	1,836	$	9	$	12	$	1,833
Mortgage-backed securities	616		2		4		614
Asset-backed securities	248		—		1		247
Municipal securities	123		1		1		123
U.S. Treasury notes	353		—		—		353
Other	32		—		—		32
Total	$	3,208	$	12	$	18	$	3,202

Schedule of Contractual Maturities of Investments

The contractual maturities of our current investments as of September 30, 2022 are summarized below:

	Amortized Cost		Estimated Fair Value
	(In millions)
Due in one year or less	$	378	$	374
Due after one year through five years	2,330		2,186
Due after five years through ten years	390		364
Due after ten years	784		715
Total	$	3,882	$	3,639

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, 2022:

	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	$	1,764	$	103	909	$	433	$	45	167
Mortgage-backed securities	555		36		282	188		25		75
Asset-backed securities	242		13		128	56		6		28
Municipal securities	106		7		110	31		4		35
U.S. Treasury notes	116		1		8	—		—		—
Other	32		3		20	—		—		—
Total	$	2,815	$	163	1,457	$	708	$	80	305

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 December 31, 2021:

	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	$	1,063	$	12	395	$	—	$	—	—
Mortgage-backed securities	408		4		146	—		—		—
Asset-backed securities	166		1		75	—		—		—
Municipal securities	69		1		61	—		—		—
Total	$	1,706	$	18	677	$	—	$	—	—