Short-term and Long-term Investments, Restricted Deposits - Narrative (Details) $ in Millions	3 Months Ended
Mar. 31, 2023 USD ($) position	Dec. 31, 2022 USD ($)
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Accrued interest income \| $	$ 141	$ 132
Positions from which gross unrealized losses were generated	6,109
Total investment positions	6,936
Commercial mortgage-backed securities
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Investments recorded at fair value that carry rating of AAA Plus, weighted average (in years)	4 years
Rated Securities \| External Credit Rating, Investment Grade \| Investment Securities
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Percentage of investments in rated securities carry an investment grade rating by nationally recognized statistical rating organizations	99.00%

Debt Securities, Available -for-Sale, Number of Positions

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- Definition

Investments Recorded At Fair Value That Carry Rating Of A AA Plus, Weighted Average, Duration

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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