Investments - Available-for-Sale Debt Securities - Narrative (Details)	3 Months Ended
Mar. 31, 2024 USD ($) investment	Mar. 31, 2023 USD ($)	Dec. 31, 2023 investment
Investments, Debt and Equity Securities [Abstract]
Debt Securities, available-for-sale, unrealized loss position, number of positions \| investment	474		385
Impairments related to credit loss	$ 0	$ 0
Sales of available-for-sale debt securities	831,800,000	$ 0
Gross realized gains	400,000
Gross realized losses	1,800,000
Net realized loss	$ 1,400,000

Amount of realized gain on 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 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-9

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

+ References

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-Topic 320
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-9

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Amount of realized loss 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.

+ References

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

+ References

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Amount of cash inflow from sale 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
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