FAIR VALUE DISCLOSURES - Carrying Values and Fair Values of Financial Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage loans on real estate	$ 12,100	$ 11,818
Loans to affiliates	600	600
Policyholders’ liabilities: Investment contracts	48,593	46,403
Policy loans	3,253	3,267
Loans from affiliates	0	572
Separate Accounts liabilities	118,130	108,487
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage loans on real estate	12,100	11,818
FHLBNY Funding Agreements	4,001	4,002
Loans to affiliates	600	600
Policyholders’ liabilities: Investment contracts	1,983	1,974
Policy loans	3,253	3,267
Loans from affiliates		572
Separate Accounts liabilities	8,173	7,406
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage loans on real estate	12,002	11,478
FHLBNY Funding Agreements	4,011	3,956
Loans to affiliates	610	603
Policyholders’ liabilities: Investment contracts	2,094	2,015
Policy loans	4,064	3,944
Loans from affiliates		572
Separate Accounts liabilities	8,173	7,406
Fair Value \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage loans on real estate	0	0
FHLBNY Funding Agreements	0	0
Loans to affiliates	0	0
Policyholders’ liabilities: Investment contracts	0	0
Policy loans	0	0
Loans from affiliates		0
Separate Accounts liabilities	0	0
Fair Value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage loans on real estate	0	0
FHLBNY Funding Agreements	4,011	3,956
Loans to affiliates	610	603
Policyholders’ liabilities: Investment contracts	0	0
Policy loans	0	0
Loans from affiliates		572
Separate Accounts liabilities	0	0
Fair Value \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage loans on real estate	12,002	11,478
FHLBNY Funding Agreements	0	0
Loans to affiliates	0	0
Policyholders’ liabilities: Investment contracts	2,094	2,015
Policy loans	4,064	3,944
Loans from affiliates		0
Separate Accounts liabilities	$ 8,173	$ 7,406

For an unclassified balance sheet, amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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Amount of the reinsurer's funds held on its behalf by the ceding insurer, including funds held in trust, under reinsurance treaties or contracts with the assuming insurer as security for the payment of the obligations thereunder.

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