OFFSETTING OF ASSETS AND LIABILITIES - Schedule of Derivative Instruments by Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Derivative instruments by assets
Fair value of non-cash collateral	$ 29,500	$ 21,300
Offsetting of Assets
Gross Amounts of Recognized Assets, Derivatives Not Subject to a master netting arrangement	1,407,774	995,493
Gross Amounts Offset in the Balance Sheets	0	0
Net Amounts of Assets Presented in the Balance Sheets	1,407,774	995,493
Gross Amounts Not Offset in the statement of Financial Position, Financial Instruments, subject to master netting arrangement	537,340	452,562
Gross Amounts Not Offset in the Statement of Financial Position, Cash collateral received	391,941	215,587
Net Amount	478,493	327,344
Free-Standing derivatives
Offsetting of Assets
Gross Amounts of Recognized Assets, subject to master netting arrangement	1,087,780	785,650
Gross Amounts Offset in the Balance Sheets	0	0
Net Amounts of Assets Presented in the Balance Sheets	1,087,780	785,650
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments, not subject to master netting arrangement	537,340	452,562
Gross Amounts Not Offset in the Statement of Financial Position, Cash collateral received	391,941	215,587
Net Amount	158,499	117,501
Total derivatives, subject to a master netting arrangement or similar arrangement
Offsetting of Assets
Gross Amounts of Recognized Assets, subject to master netting arrangement	1,087,780	785,650
Gross Amounts Offset in the Balance Sheets	0	0
Net Amounts of Assets Presented in the Balance Sheets	1,087,780	785,650
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments, not subject to master netting arrangement	537,340	452,562
Gross Amounts Not Offset in the Statement of Financial Position, Cash collateral received	391,941	215,587
Net Amount	158,499	117,501
Embedded derivative - Modco reinsurance treaties
Offsetting of Assets
Gross Amounts of Recognized Assets, Derivatives Not Subject to a master netting arrangement	83,379	31,926
Gross Amounts Offset in the Balance Sheets	0	0
Net Amounts of Assets Presented in the Balance Sheets	83,379	31,926
Gross Amounts Not Offset in the statement of Financial Position, Financial Instruments, subject to master netting arrangement	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Cash collateral received	0	0
Net Amount	83,379	31,926
Embedded derivative - GLWB
Offsetting of Assets
Gross Amounts of Recognized Assets, Derivatives Not Subject to a master netting arrangement	48,091	62,538
Gross Amounts Offset in the Balance Sheets	0	0
Net Amounts of Assets Presented in the Balance Sheets	48,091	62,538
Gross Amounts Not Offset in the statement of Financial Position, Financial Instruments, subject to master netting arrangement	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Cash collateral received	0	0
Net Amount	48,091	62,538
Derivatives with PLC
Offsetting of Assets
Gross Amounts of Recognized Assets, Derivatives Not Subject to a master netting arrangement	133,486	115,379
Gross Amounts Offset in the Balance Sheets	0	0
Net Amounts of Assets Presented in the Balance Sheets	133,486	115,379
Gross Amounts Not Offset in the statement of Financial Position, Financial Instruments, subject to master netting arrangement	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Cash collateral received	0	0
Net Amount	133,486	115,379
Other
Offsetting of Assets
Gross Amounts of Recognized Assets, Derivatives Not Subject to a master netting arrangement	55,038	0
Gross Amounts Offset in the Balance Sheets	0	0
Net Amounts of Assets Presented in the Balance Sheets	55,038	0
Gross Amounts Not Offset in the statement of Financial Position, Financial Instruments, subject to master netting arrangement	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Cash collateral received	0	0
Net Amount	55,038	0
Total derivatives, not subject to a master netting arrangement or similar arrangement
Offsetting of Assets
Gross Amounts of Recognized Assets, Derivatives Not Subject to a master netting arrangement	319,994	209,843
Gross Amounts Offset in the Balance Sheets	0	0
Net Amounts of Assets Presented in the Balance Sheets	319,994	209,843
Gross Amounts Not Offset in the statement of Financial Position, Financial Instruments, subject to master netting arrangement	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Cash collateral received	0	0
Net Amount	$ 319,994	$ 209,843

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

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