EQUITY - Cumulative Gains (Losses) (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss) attributable to Holdings	$ 1,860	$ 1,466	$ 4,205	$ 3,423
Total accumulated other comprehensive income (loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss) attributable to Holdings	(6,327)	(6,305)
Unrealized gains (losses) on investments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss) attributable to Holdings	(5,511)	(4,722)
Market risk benefits - instrument-specific credit risk component
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss) attributable to Holdings	(507)	(1,166)
Liability for future policy benefits - current discount rate component
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss) attributable to Holdings	280	204
Defined benefit pension plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss) attributable to Holdings	(525)	(563)
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss) attributable to Holdings	(64)	(58)
Less: Accumulated other comprehensive income (loss) attributable to noncontrolling interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss) attributable to Holdings	(27)	(25)
Accumulated other comprehensive income (loss) attributable to Holdings
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss) attributable to Holdings	$ (6,300)	$ (6,280)	$ (7,567)	$ (8,712)