DERIVATIVES - Derivative Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	$ 97,210,442	$ 84,622,876
Derivative Assets
Fair value included within total assets and liabilities, derivative asset	315,069	315,107
Derivative Liabilities
Fair value included within total assets and liabilities, derivative liabilities	530,472	590,187
Asset Management and Strategic Holdings
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	18,572,843	16,146,067
Derivative Assets
Gross Amount Recognized	284,062	269,413
Derivative Liabilities
Gross Amount Recognized	226,310	443,990
Asset Management and Strategic Holdings | Foreign Currency Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	17,586,779	15,771,463
Derivative Assets
Gross Amount Recognized	274,943	264,621
Derivative Liabilities
Gross Amount Recognized	226,240	441,608
Asset Management and Strategic Holdings | Other Derivatives
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	986,064	374,604
Derivative Assets
Gross Amount Recognized	9,119	4,792
Derivative Liabilities
Gross Amount Recognized	70	2,382
Insurance
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	78,637,599	68,476,809
Derivative Assets
Gross Amount Recognized	2,073,783	1,855,023
Impact of Netting	(2,042,776)	(1,809,329)
Net Amounts Presented in the Statements of Financial Condition	31,007	45,694
Derivative Liabilities
Gross Amount Recognized	1,037,481	1,057,277
Impact of Netting	(733,319)	(911,080)
Net Amounts Presented in the Statements of Financial Condition	304,162	146,197
Insurance | Assets
Derivative Liabilities
Fair value of embedded derivatives, net	114,300	88,700
Insurance | Liability
Derivative Liabilities
Fair value of embedded derivatives, net	2,100,000	1,600,000
Insurance | Derivatives Designated as Hedge Accounting Instruments:
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	11,870,309	9,622,835
Derivative Assets
Gross Amount Recognized	32,974	24,278
Derivative Liabilities
Gross Amount Recognized	435,996	445,690
Insurance | Derivatives Not Designated as Hedge Accounting Instruments:
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	66,767,290	58,853,974
Derivative Assets
Gross Amount Recognized	2,040,809	1,830,745
Derivative Liabilities
Gross Amount Recognized	601,485	611,587
Insurance | Foreign Currency Contracts | Derivatives Designated as Hedge Accounting Instruments:
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	2,414,567	2,302,335
Derivative Assets
Gross Amount Recognized	28,133	24,278
Derivative Liabilities
Gross Amount Recognized	24,903	73,478
Insurance | Foreign Currency Contracts | Derivatives Not Designated as Hedge Accounting Instruments:
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	2,536,288	1,331,345
Derivative Assets
Gross Amount Recognized	68,301	65,803
Derivative Liabilities
Gross Amount Recognized	60,284	56,616
Insurance | Interest Rate Contracts | Derivatives Designated as Hedge Accounting Instruments:
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	9,455,742	7,320,500
Derivative Assets
Gross Amount Recognized	4,841	0
Derivative Liabilities
Gross Amount Recognized	411,093	372,212
Insurance | Interest Rate Contracts | Derivatives Not Designated as Hedge Accounting Instruments:
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	28,197,299	22,259,423
Derivative Assets
Gross Amount Recognized	153,008	284,067
Derivative Liabilities
Gross Amount Recognized	352,870	306,244
Insurance | Equity Market Contracts | Derivatives Not Designated as Hedge Accounting Instruments:
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	35,972,616	35,203,206
Derivative Assets
Gross Amount Recognized	1,819,500	1,480,875
Derivative Liabilities
Gross Amount Recognized	185,033	248,127
Insurance | Other contracts | Derivatives Not Designated as Hedge Accounting Instruments:
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	61,087	60,000
Derivative Assets
Gross Amount Recognized	0	0
Derivative Liabilities
Gross Amount Recognized	$ 3,298	$ 600