INVESTMENTS - Fixed Maturities Held To Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss [Abstract]
Amortized cost	$ 446,016	$ 0
Allowance for expected credit losses	0
Net carrying value	446,016
Gross unrealized gains	99
Gross unrealized losses	(1,082)
Fair value	445,033	$ 0
Corporate debt
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss [Abstract]
Amortized cost	37,700
Allowance for expected credit losses	0
Net carrying value	37,700
Gross unrealized gains	18
Gross unrealized losses	(146)
Fair value	37,572
ABS
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss [Abstract]
Amortized cost	408,316
Allowance for expected credit losses	0
Net carrying value	408,316
Gross unrealized gains	81
Gross unrealized losses	(936)
Fair value	$ 407,461