FAIR VALUE OF FINANCIAL INSTRUMENTS - Estimated Fair Value of Financial Instruments (Details) - Successor - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Assets:
Mortgage loans on real estate	$ 6,132,125	$ 5,662,812
Policy loans	1,650,240	1,699,508
Fixed maturities, held-to-maturity	2,770,177	593,314
Liabilities:
Stable value product account balances	3,501,636	2,131,822
Annuity account balances	10,642,115	10,719,862
Other policyholders' funds	1,165,749	1,069,572
Debt:
Subordinated debt securities	441,202	448,763
Non-recourse funding obligations	2,796,474	685,684
Golden Gate V
Debt:
Non-recourse funding obligations	628,025	564,679
Carrying Amounts
Assets:
Mortgage loans on real estate	6,132,125	5,662,812
Policy loans	1,650,240	1,699,508
Fixed maturities, held-to-maturity	2,770,177	593,314
Liabilities:
Stable value product account balances	3,501,636	2,131,822
Annuity account balances	221,634	226,499
Other policyholders' funds	135,367	132,840
Debt:
Bank borrowings	170,000	485,000
Senior Notes	993,285	1,103,806
Subordinated debt securities	441,202	448,763
Non-recourse funding obligations	2,796,474	685,684
Carrying Amounts \| Golden Gate V
Debt:
Non-recourse funding obligations	565,000	500,000
Fair Values \| Golden Gate V
Debt:
Non-recourse funding obligations	567,100	495,500
Fair Values \| Level 3
Assets:
Mortgage loans on real estate	5,930,992	5,529,803
Policy loans	1,650,240	1,699,508
Fixed maturities, held-to-maturity	2,733,340	515,000
Liabilities:
Stable value product account balances	3,488,877	2,124,712
Annuity account balances	221,658	226,527
Other policyholders' funds	136,127	133,657
Debt:
Bank borrowings	170,000	485,000
Non-recourse funding obligations	2,765,558	614,380
Fair Values \| Level 2
Debt:
Senior Notes	937,074	1,020,025
Subordinated debt securities	$ 443,355	$ 457,275

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Non-recourse funding obligations issued by special purpose entities owned by the reporting entity. The funding obligations are direct financial obligations of the special purpose entity and are not guaranteed by the reporting entity.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Amount before allowance of loans made to policy and contract holders using their life insurance contracts' cash value or separate accounts as collateral. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums over and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the normal operating cycle if longer.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Amount due to policyholders for funds held that are returnable under the terms of insurance contracts, classified as other.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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