OTHER COMPREHENSIVE INCOME (LOSS) - Reclassifications out of AOCI into net income (Details) - USD ($) $ in Thousands		12 Months Ended
	Dec. 18, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reclassification out of accumulated comprehensive income into net income available to common shareholders [Line Items]
Impairment losses		$ (22)	$ (1,486)	$ 0
Other-than-temporary impairment ("OTTI") losses		0	0	(6,984)
Income before income taxes and interest in income of equity method investments		648,909	(129,133)	337,447
Foreign exchange losses		(315)	(81,069)	12,041
Income tax (expense) benefit		(62,384)	12,321	(23,692)
Net income (loss)		618,609	(120,424)	323,473
Reclassification out of Accumulated Other Comprehensive Income | Unrealized gains (losses) on available for sale investments
Reclassification out of accumulated comprehensive income into net income available to common shareholders [Line Items]
Other realized gains (losses)		94,771	91,866	36,602
Impairment losses		(22)	(1,486)	0
Other-than-temporary impairment ("OTTI") losses		0	0	(6,984)
Income before income taxes and interest in income of equity method investments		94,749	90,380	29,618
Income tax (expense) benefit		(7,635)	(12,368)	(4,889)
Net income (loss)		87,114	78,012	24,729
Reclassification out of Accumulated Other Comprehensive Income | Foreign currency translation adjustment
Reclassification out of accumulated comprehensive income into net income available to common shareholders [Line Items]
Foreign exchange losses		0	0	6,043
Income tax (expense) benefit		0	0	0
Net income (loss)		$ 0	$ 0	$ 6,043
Reclassification out of Accumulated Other Comprehensive Income | Foreign currency translation adjustment | Aviabel
Reclassification out of accumulated comprehensive income into net income available to common shareholders [Line Items]
Foreign exchange losses	$ 6,000