SHAREHOLDERS' EQUITY - Reclassifications Out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)		$ 122	$ 307
Acquisition and operating expenses		(1,509)	(1,531)
Income tax (expense) or benefit		(244)	(310)
Net of tax		$ 1,032	$ 1,293
U.S. federal statutory income tax rate		21.00%	21.00%
Reclassification Out Of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net of tax		$ 55	$ (24)
Reclassification Out Of Accumulated Other Comprehensive Income | Unrealized gains (losses) on available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)		77	(20)
Income tax (expense) or benefit	[1]	(16)	4
Net of tax		61	(16)
Reclassification Out Of Accumulated Other Comprehensive Income | Unrealized gains (losses) on derivatives
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)		(1)
Income tax (expense) or benefit	[1]	0
Net of tax		(1)
Reclassification Out Of Accumulated Other Comprehensive Income | Pension liability adjustment, actuarial gains (losses)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Acquisition and operating expenses	[2]	(6)	(10)
Reclassification Out Of Accumulated Other Comprehensive Income | Pension liability adjustment, prior service (cost) credit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Acquisition and operating expenses	[2]	0	0
Reclassification Out Of Accumulated Other Comprehensive Income | Pension liability adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax (expense) or benefit	[1]	1	2
Net of tax		$ (5)	$ (8)

[1] Based on 21% tax rate

[2] These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 11 for additional details).