OFFSETTING OF ASSETS AND LIABILITIES - Schedule of Derivative Instruments by Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Offsetting of Assets
Gross Amounts of Recognized Assets	$ 545,645	$ 542,243
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	545,645	542,243
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	206,954	171,384
Gross Amounts Not Offset in the Statement of Financial Position, Cash Collateral Received	96,785	100,890
Net Amount	241,906	269,969
Free-Standing derivatives
Offsetting of Assets
Gross Amounts of Recognized Assets	412,064	417,769
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	412,064	417,769
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	206,954	171,384
Gross Amounts Not Offset in the Statement of Financial Position, Cash Collateral Received	96,785	100,890
Net Amount	108,325	145,495
Total derivatives, subject to a master netting arrangement or similar arrangement
Offsetting of Assets
Gross Amounts of Recognized Assets	412,064	417,769
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	412,064	417,769
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	206,954	171,384
Gross Amounts Not Offset in the Statement of Financial Position, Cash Collateral Received	96,785	100,890
Net Amount	108,325	145,495
Embedded derivative - Modco reinsurance treaties
Offsetting of Assets
Gross Amounts of Recognized Assets	616	2,573
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	616	2,573
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Cash Collateral Received	0	0
Net Amount	616	2,573
Embedded derivative - GLWB
Offsetting of Assets
Gross Amounts of Recognized Assets	132,812	121,752
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	132,812	121,752
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Cash Collateral Received	0	0
Net Amount	132,812	121,752
Other
Offsetting of Assets
Gross Amounts of Recognized Assets	153	149
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	153	149
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Cash Collateral Received	0	0
Net Amount	153	149
Total derivatives, not subject to a master netting arrangement or similar arrangement
Offsetting of Assets
Gross Amounts of Recognized Assets	133,581	124,474
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	133,581	124,474
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Cash Collateral Received	0	0
Net Amount	$ 133,581	$ 124,474

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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Fair value of liability associated with 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.

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