RESERVE FOR CLAIMS AND CLAIM EXPENSES - Schedule of Liability for Unpaid Claims and Claims Adjustment Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Reserve for claims and claim expenses, net of reinsurance recoverable, as of beginning of period			$ 11,181,648	$ 9,025,961
Net incurred related to:
Current year	$ 963,309	$ 749,196	1,869,261	1,608,762
Prior years	(32,098)	(42,957)	(136,850)	(60,790)
Total net incurred	931,211	706,239	1,732,411	1,547,972
Net paid related to:
Current year			92,909	41,124
Prior years			1,406,684	1,129,979
Total net paid			1,499,593	1,171,103
Foreign exchange			34,311	(166,483)
Reserve for claims and claim expenses, net of reinsurance recoverable, as of end of period	11,448,777	9,236,347	11,448,777	9,236,347
Reinsurance recoverable as of end of period	4,689,351	4,206,459	4,689,351	4,206,459	$ 4,710,925
Reserve for claims and claim expenses as of end of period	$ 16,138,128	$ 13,442,806	$ 16,138,128	$ 13,442,806