v3.25.4

INVESTMENTS - Summary of investments in a gross unrealized loss position (Details) $ in Thousands	Dec. 31, 2025 USD ($) security	Dec. 31, 2024 USD ($) security
Less than 12 Months
Number of Securities \| security	107	301
Fair Value	$ 347,677	$ 877,287
Gross Unrealized Losses	$ (495)	$ (9,802)
12 Months or Longer
Number of Securities \| security	5	6
Fair Value	$ 40,784	$ 47,748
Gross Unrealized Losses	$ (120)	$ (25)
U.S. treasury and agency securities
Less than 12 Months
Number of Securities \| security	48	191
Fair Value	$ 265,431	$ 730,938
Gross Unrealized Losses	$ (445)	$ (9,003)
12 Months or Longer
Number of Securities \| security	5	6
Fair Value	$ 40,784	$ 47,748
Gross Unrealized Losses	$ (120)	$ (25)
Corporate notes
Less than 12 Months
Number of Securities \| security	59	110
Fair Value	$ 82,246	$ 146,349
Gross Unrealized Losses	$ (50)	$ (799)
12 Months or Longer
Number of Securities \| security	0	0
Fair Value	$ 0	$ 0
Gross Unrealized Losses	$ 0	$ 0

Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer

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- Definition

Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months

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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), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 55
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-Topic 326
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- Definition

Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

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-Topic 320
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-Section 50
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- Definition

Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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 continuous unrealized loss position for less than 12 months, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Oscar Health, Inc. 10-K