SEGMENT REPORTING - Schedule of Breakdown By Revenue (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Segment Reporting [Line Items]
Total revenue	$ 4,217	$ 3,037	$ 5,873	$ 5,655
U.S.
Segment Reporting [Line Items]
Total revenue	2,331	2,570	4,603	5,087
U.K.
Segment Reporting [Line Items]
Total revenue	1,313	3	1,327	2
Bermuda
Segment Reporting [Line Items]
Total revenue	32	105	86	84
Canada
Segment Reporting [Line Items]
Total revenue	436	61	502	155
Other
Segment Reporting [Line Items]
Total revenue	$ 105	$ 298	$ (645)	$ 327

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details

- 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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+ Details