FAIR VALUE MEASUREMENTS (Details - Quantitative Information about Level 3 Fair Value Measurements, Assets) $ in Millions	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Obligations of states, municipalities and political subdivisions | Minimum | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0337	0.0335
Obligations of states, municipalities and political subdivisions | Maximum | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0413	0.0395
Obligations of states, municipalities and political subdivisions | Weighted-average | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0375	0.0365
Obligations of states, municipalities and political subdivisions | Discounted cash flow | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 1,616	$ 1,633
Corporate debt | Minimum | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0211	0.0348
Corporate debt | Maximum | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0618	0.0622
Corporate debt | Weighted-average | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0414	0.0485
Corporate debt | Discounted cash flow | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 982	$ 1,087
Residential mortgage-backed securities | Minimum | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0401	0.0252
Residential mortgage-backed securities | Minimum | Measurement Input Constant Prepayment Rate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0446	0.0400
Residential mortgage-backed securities | Minimum | Measurement Input Loss Severity [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.3078	0.3368
Residential mortgage-backed securities | Minimum | Measurement Input Constant Default Rate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0141	0.0168
Residential mortgage-backed securities | Maximum | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0689	0.0453
Residential mortgage-backed securities | Maximum | Measurement Input Constant Prepayment Rate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.1312	0.1289
Residential mortgage-backed securities | Maximum | Measurement Input Loss Severity [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.7629	0.7691
Residential mortgage-backed securities | Maximum | Measurement Input Constant Default Rate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0586	0.0617
Residential mortgage-backed securities | Weighted-average | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0545	0.0352
Residential mortgage-backed securities | Weighted-average | Measurement Input Constant Prepayment Rate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0879	0.0844
Residential mortgage-backed securities | Weighted-average | Measurement Input Loss Severity [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.5353	0.5529
Residential mortgage-backed securities | Weighted-average | Measurement Input Constant Default Rate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0363	0.0393
Residential mortgage-backed securities | Discounted cash flow | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 10,762	$ 11,746
Certain CDO/ABS | Minimum | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0393	0.0292
Certain CDO/ABS | Maximum | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0794	0.0491
Certain CDO/ABS | Weighted-average | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0594	0.0391
Certain CDO/ABS | Discounted cash flow | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 6,914	$ 6,025
Commercial mortgage backed securities | Minimum | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0106	0.0277
Commercial mortgage backed securities | Maximum | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0694	0.0518
Commercial mortgage backed securities | Weighted-average | Measurement Input Yield [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.0400	0.0397
Commercial mortgage backed securities | Discounted cash flow | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 555	$ 476