Equity Securities (Tables)

12 Months Ended

Dec. 31, 2022

Investments, Debt and Equity Securities [Abstract]

Summary of Investments in Equity Securities, by Classification

Investments in equity securities, by classification, are summarized as follows:

	December 31,
(in millions)	2022		2021
Marketable equity securities	$	280	$	657
Non-marketable equity securities		396		441
Equity method investments		78		78
	$	754	$	1,176

Summary of Investments in Marketable Equity Securities

Investments in marketable equity securities are summarized as follows:

(in millions)	Cost		Unrealized gains (losses)			Estimated fair value
December 31, 2022
Common stocks	$	324	$	(55	)	$	269
Preferred stocks		15		(4	)		11
	$	339	$	(59	)	$	280
December 31, 2021
Common stocks	$	418	$	222		$	640
Preferred stocks		17		—			17
	$	435	$	222		$	657

Summary of Investments in Non-Marketable Equity Securities

Investments in non-marketable equity securities are summarized as follows:

(in millions)	Cost		Unrealized gains		Carrying amount
December 31, 2022	$	307	$	89	$	396
December 31, 2021	$	215	$	226	$	441