SIGNIFICANT ACCOUNTING POLICIES - Schedule of Deferred Income (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021	Dec. 31, 2020
Deferred Sale Inducement Cost [Line Items]
Sales Inducement Assets					$ 404
Previously Reported
Deferred Sale Inducement Cost [Line Items]
Sales Inducement Assets					404
Adjustment for reversal of balances recorded in Accumulated Other Comprehensive Income
Deferred Sale Inducement Cost [Line Items]
Sales Inducement Assets					0
Protection Solutions
Deferred Sale Inducement Cost [Line Items]
Unearned Revenue Liability					541
Protection Solutions | Previously Reported
Deferred Sale Inducement Cost [Line Items]
Unearned Revenue Liability					413
Protection Solutions | Adjustment for reversal of balances recorded in Accumulated Other Comprehensive Income
Deferred Sale Inducement Cost [Line Items]
Unearned Revenue Liability					128
GMxB Legacy | Legacy Segment
Deferred Sale Inducement Cost [Line Items]
Sales Inducement Assets					246
GMxB Legacy | Legacy Segment | Previously Reported
Deferred Sale Inducement Cost [Line Items]
Sales Inducement Assets					246
GMxB Legacy | Legacy Segment | Adjustment for reversal of balances recorded in Accumulated Other Comprehensive Income
Deferred Sale Inducement Cost [Line Items]
Sales Inducement Assets					0
GMxB Core
Deferred Sale Inducement Cost [Line Items]
Sales Inducement Assets	$ 129	$ 137	$ 139	$ 147
GMxB Core | Individual Retirement
Deferred Sale Inducement Cost [Line Items]
Sales Inducement Assets					158
GMxB Core | Individual Retirement | Previously Reported
Deferred Sale Inducement Cost [Line Items]
Sales Inducement Assets					158
GMxB Core | Individual Retirement | Adjustment for reversal of balances recorded in Accumulated Other Comprehensive Income
Deferred Sale Inducement Cost [Line Items]
Sales Inducement Assets					0
UL | Protection Solutions
Deferred Sale Inducement Cost [Line Items]
Unearned Revenue Liability					60
UL | Protection Solutions | Previously Reported
Deferred Sale Inducement Cost [Line Items]
Unearned Revenue Liability					31
UL | Protection Solutions | Adjustment for reversal of balances recorded in Accumulated Other Comprehensive Income
Deferred Sale Inducement Cost [Line Items]
Unearned Revenue Liability					29
VUL | Protection Solutions
Deferred Sale Inducement Cost [Line Items]
Unearned Revenue Liability					481
VUL | Protection Solutions | Previously Reported
Deferred Sale Inducement Cost [Line Items]
Unearned Revenue Liability					382
VUL | Protection Solutions | Adjustment for reversal of balances recorded in Accumulated Other Comprehensive Income
Deferred Sale Inducement Cost [Line Items]
Unearned Revenue Liability					99
IUL | Protection Solutions
Deferred Sale Inducement Cost [Line Items]
Unearned Revenue Liability					0
IUL | Protection Solutions | Previously Reported
Deferred Sale Inducement Cost [Line Items]
Unearned Revenue Liability					0
IUL | Protection Solutions | Adjustment for reversal of balances recorded in Accumulated Other Comprehensive Income
Deferred Sale Inducement Cost [Line Items]
Unearned Revenue Liability					$ 0