SHAREHOLDERS' EQUITY - Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	$ 7,393	$ 8,934
Other comprehensive income (loss) before reclassifications net of tax	(4,225)	(2,151)
Amounts reclassified from accumulated other comprehensive income net of tax	(55)	24
Other comprehensive income (loss), net of tax	(4,280)	(2,127)
Balance, end of period	3,113	6,807
Unrealized Foreign Currency Translation Gains (Losses)
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	(2,013)	(1,109)
Other comprehensive income (loss) before reclassifications net of tax	(469)	(565)
Amounts reclassified from accumulated other comprehensive income net of tax	0	0
Other comprehensive income (loss), net of tax	(469)	(565)
Balance, end of period	(2,482)	(1,674)
Unrealized Gains (Losses) on Fixed Maturity Securities
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	9,602	10,361
Other comprehensive income (loss) before reclassifications net of tax	(3,754)	(1,583)
Amounts reclassified from accumulated other comprehensive income net of tax	(61)	16
Other comprehensive income (loss), net of tax	(3,815)	(1,567)
Balance, end of period	5,787	8,794
Unrealized gains (losses) on derivatives
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	(30)	(34)
Other comprehensive income (loss) before reclassifications net of tax	0	1
Amounts reclassified from accumulated other comprehensive income net of tax	1	0
Other comprehensive income (loss), net of tax	1	1
Balance, end of period	(29)	(33)
Pension liability adjustment
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	(166)	(284)
Other comprehensive income (loss) before reclassifications net of tax	(2)	(4)
Amounts reclassified from accumulated other comprehensive income net of tax	5	8
Other comprehensive income (loss), net of tax	3	4
Balance, end of period	$ (163)	$ (280)