Fair Value Measurements - Schedule of Fair Value of Investment Assets (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	$ 181	$ 196
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Amortized Cost	184	201
Level 1 \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	80	89
Level 1 \| Fair Value \| Fixed Income Mutual Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	80	89
Level 1 \| Fair Value \| Corporate Bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	0	0
Level 1 \| Fair Value \| Government Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	0	0
Level 2 \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	101	107
Level 2 \| Fair Value \| Fixed Income Mutual Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	0	0
Level 2 \| Fair Value \| Corporate Bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	60	49
Level 2 \| Fair Value \| Government Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	41	58
Total \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	181	196
Total \| Fair Value \| Fixed Income Mutual Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	80	89
Total \| Fair Value \| Corporate Bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	60	49
Total \| Fair Value \| Government Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	$ 41	$ 58

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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