OTHER COMPREHENSIVE INCOME (LOSS) - Summary of Tax Effects Allocated to Each Component of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Before tax amount
Unrealized gains (losses) arising during the year, net of reclassification adjustment	$ 125,742	$ 448,477	$ (909,150)
Foreign currency translation adjustment	(23,763)	(1,572)	(10,986)
Total other comprehensive income (loss), net of tax	101,979	446,905	(920,136)
Income tax (expense) benefit
Unrealized gains (losses) arising during the year, net of reclassification adjustment	(3,700)	(52,441)	103,300
Foreign currency translation adjustment	0	0	0
Total other comprehensive income (loss), net of tax	(3,700)	(52,441)	103,300
Net of tax amount
Unrealized gains (losses) arising during the year, net of reclassification adjustment	122,042	396,036	(805,850)
Foreign currency translation adjustment	(23,763)	(1,572)	(10,986)
Total other comprehensive income (loss), net of tax	98,279	394,464	(816,836)
Available for sale investments
Before tax amount
Adjustment for reclassification of net realized (gains) losses and impairment losses recognized in net income (loss)	170,984	142,324	335,294
Income tax (expense) benefit
Adjustment for reclassification of net realized (gains) losses and impairment losses recognized in net income (loss)	(15,664)	(13,811)	(30,369)
Net of tax amount
Adjustment for reclassification of net realized (gains) losses and impairment losses recognized in net income (loss)	155,320	128,513	304,925
Unrealized gains (losses) arising during the year, net of reclassification adjustment	122,042	396,036	(805,850)
Available for sale investments | Unrealized gains (losses) arising during the year for which an allowance for expected credit losses has not been recognized
Before tax amount
Unrealized gains (losses) arising during the period	(44,964)	294,933	(1,171,381)
Income tax (expense) benefit
Unrealized gains (losses) arising during the period	11,934	(36,993)	127,756
Net of tax amount
Unrealized gains (losses) arising during the period	(33,030)	257,940	(1,043,625)
Available for sale investments | Unrealized gains (losses) arising during the year for which an allowance for expected credit losses has been recognized
Before tax amount
Unrealized gains (losses) arising during the period	(278)	11,220	(73,063)
Income tax (expense) benefit
Unrealized gains (losses) arising during the period	30	(1,637)	5,913
Net of tax amount
Unrealized gains (losses) arising during the period	$ (248)	$ 9,583	$ (67,150)