Investments - Investment Segment - Ownership (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Summary of Investment Holdings [Line Items]
Fair value of investments	$ 2,141		$ 3,137
Gains (Losses) Recognized in Income	$ (1,445)	$ (47)
Herbalife
Summary of Investment Holdings [Line Items]
Voting Interests	23.90%
Fair value of investments	$ 1,027		1,343
Gains (Losses) Recognized in Income	$ (515)	(168)
Hertz
Summary of Investment Holdings [Line Items]
Voting Interests	38.90%
Fair value of investments	$ 342		551
Gains (Losses) Recognized in Income	$ (335)	95
Caesars
Summary of Investment Holdings [Line Items]
Voting Interests	16.70%
Fair value of investments	$ 772		$ 1,243
Gains (Losses) Recognized in Income	$ (595)	$ 26

Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
-Paragraph 6
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-URI http://asc.fasb.org/extlink&oid=99383244&loc=d3e12121-115841

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 4
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 6
-Subparagraph (SX 210.12-14.Column E.2,3)
-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611322-123010

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 1
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 5
-Subparagraph (SX 210.12-13.Column C.6)
-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611282-123010

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