Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(3)(d))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=123583765&loc=SL75117546-209714

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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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Investments - Other Segments and Holding Company (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Schedule of Investments
Investments	$ 6,637		$ 6,809
Other Segments and Holding Company
Schedule of Investments
Investments	117		90
Portion of unrealized (losses) gains that relates to equity securities still held	0	$ 58
Equity method investments \| Other Segments and Holding Company
Schedule of Investments
Investments	103		76
Other investments \| Other Segments and Holding Company
Schedule of Investments
Investments	$ 14		$ 14