Fair Value Measurements - Schedule of Fair Value of Investment Assets (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	$ 5	$ 5
Level 1 \| Exchange-traded Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	5	5
Level 1 \| Time Deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	0	0
Level 1 \| Corporate Bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	0	0
Level 1 \| Government Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	0	0
Level 1 \| Asset-backed Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	0	0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	298	182
Level 2 \| Exchange-traded Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	0	0
Level 2 \| Time Deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	140	0
Level 2 \| Corporate Bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	69	82
Level 2 \| Government Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	69	71
Level 2 \| Asset-backed Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	20	29
Total
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	303	187
Total \| Exchange-traded Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	5	5
Total \| Time Deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	140	0
Total \| Corporate Bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	69	82
Total \| Government Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	69	71
Total \| Asset-backed Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	$ 20	$ 29

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