INVESTMENTS

3 Months Ended

Mar. 31, 2024

Investments, Debt and Equity Securities [Abstract]

The following tables summarize our financial instruments by significant categories and fair value measurement on a recurring basis as of March 31, 2024 and December 31, 2023 and the amortized cost, gross unrealized gains, gross unrealized losses, fair value of our AFS investments:


(in millions)	Fair Value Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Cash and Cash Equivalents		Investments		Restricted Cash, Cash Equivalents and Investments
March 31, 2024
Cash equivalents:
Money market mutual funds	Level 1	$	327	$	—	$	—	$	327	$	40	$	—	$	287
U.S. treasuries	Level 2	4		—		—		4		1		—		3
Total cash equivalents		331		—		—		331		41		—		290
AFS Investments:
Asset-backed securities	Level 2	38		—		—		38		—		38		—
Corporate bonds	Level 2	148		—		—		148		—		115		33
Agency securities	Level 2	37		—		(1)		36		—		8		28
U.S. treasuries	Level 2	260		—		(4)		256		—		77		179
Certificate of deposit	Level 2	2		—		—		2		—		—		2
Other debt securities	Level 2	8		—		—		8		—		8		—
Total AFS Investments		$	493	$	—	$	(5)	$	488	$	—	$	246	$	242


(in millions)	Fair Value Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Cash and Cash Equivalents		Investments		Restricted Cash, Cash Equivalents and Investments
December 31, 2023
Cash equivalents:
Money market mutual funds	Level 1	$	183	$	—	$	—	$	183	$	96	$	—	$	87
U.S. treasuries	Level 2	7		—		—		7		5		—		2
Total cash equivalents		190		—		—		190		101		—		89
AFS Investments:
Asset-backed securities	Level 2	41		—		(1)		40		—		40		—
Corporate bonds	Level 2	135		1		—		136		—		103		33
Agency securities	Level 2	40		—		(1)		39		—		10		29
U.S. treasuries	Level 2	231		1		(1)		231		—		47		184
Certificate of deposit	Level 2	2		—		—		2		—		—		2
Other debt securities	Level 2	8		—		—		8		—		8		—
Total AFS Investments		$	457	$	2	$	(3)	$	456	$	—	$	208	$	248

Fair Value of Financial Instruments

We use an independent pricing source to determine the fair value of our securities. The independent pricing source utilizes various pricing models for each asset class, including the market approach. The inputs and assumptions for the pricing models are market observable inputs including trades of comparable securities, dealer quotes, credit spreads, yield curves and other market-related data.

We have not adjusted the prices obtained from the independent pricing service and we believe the prices received from the independent pricing service are representative of the prices that would be received to sell the assets at the measurement date (exit price).

The carrying value of the Company's cash equivalents and restricted cash equivalents approximate their fair values due to their short-term maturities.

We did not have any Level 3 financial instruments recognized in our condensed consolidated balance sheets as of March 31, 2024 and December 31, 2023. There were no transfers between levels as of March 31, 2024 and December 31, 2023.

Sales and Maturities

The fair value of debt investments by contractual maturity are shown below:


(in millions)	March 31, 2024
One year or less	$	113
Over one year through five years	347
Over five years through ten years	10
Over ten years	18
Total fair value	$	488

The gross proceeds from sales and maturities of AFS securities for the three months ended March 31, 2024 and March 31, 2023 are presented below. We had immaterial gross realized gains and losses from sales of investments for the first quarter of 2024 and immaterial gross realized gains for the first quarter of 2023.


	Three Months Ended March 31,
(in millions)	2024		2023


Gross proceeds from sales	$	39	$	32
Gross proceeds from maturities	27		44
Total	$	66	$	76

Fair Value of Long-Term Debt

The fair value of our 2029 Notes and 2031 Notes was obtained from a third-party pricing service and is based on observable market inputs. As such, the fair value of the senior notes is considered Level 2 in the hierarchy for fair value measurement. As of March 31, 2024, our 2029 Notes and 2031 Notes were carried at their cost, net of issuance costs, and had a fair value of $449 million and $411 million, respectively. As of December 31, 2023, our 2029 Notes and 2031 Notes were carried at their cost, net of issuance costs, and had a fair value of $443 million and $414 million, respectively.

Our 2021 Revolver is a floating rate debt. At March 31, 2024 and December 31, 2023, the fair value of our 2021 Revolver approximated its carrying value (exclusive of issuance costs). The fair value of our floating rate debt is estimated based on a discounted cash flow, which incorporates credit spreads, market interest rates and contractual maturities to estimate the fair value and is considered Level 3 in the hierarchy for fair value measurement.