INVESTMENTS - Schedule of Investments in a Gross Unrealized Loss Position (Details) $ in Thousands	Jun. 30, 2026 USD ($) security	Dec. 31, 2025 USD ($) security
Less than 12 Months
Number of Securities \| security	605	107
Fair Value	$ 3,318,389	$ 347,677
Gross Unrealized Losses	$ (9,924)	$ (495)
12 Months or Longer
Number of Securities \| security	2	5
Fair Value	$ 19,821	$ 40,784
Gross Unrealized Losses	$ (310)	$ (120)
U.S. treasury and agency securities
Less than 12 Months
Number of Securities \| security	298	48
Fair Value	$ 2,659,228	$ 265,431
Gross Unrealized Losses	$ (8,033)	$ (445)
12 Months or Longer
Number of Securities \| security	2	5
Fair Value	$ 19,821	$ 40,784
Gross Unrealized Losses	$ (310)	$ (120)
Corporate notes
Less than 12 Months
Number of Securities \| security	289	59
Fair Value	$ 634,759	$ 82,246
Gross Unrealized Losses	$ (1,855)	$ (50)
12 Months or Longer
Number of Securities \| security	0	0
Fair Value	$ 0	$ 0
Gross Unrealized Losses	$ 0	$ 0
Asset-backed securities
Less than 12 Months
Number of Securities \| security	18
Fair Value	$ 24,402
Gross Unrealized Losses	$ (36)
12 Months or Longer
Number of Securities \| security	0
Fair Value	$ 0
Gross Unrealized Losses	$ 0

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

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

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

+ References

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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 12 months or longer, 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 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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