Fair Value of Financial Instruments (Fair Value Inputs Quantitative Information) (Details) - Significant Unobservable Inputs (Level 3) [Member] - Discounted Cash Flow Valuation Technique [Member] $ in Millions	Sep. 30, 2019 USD ($) item
Corporate Bonds [Member] | Fixed Maturity Securities [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure | $	$ 2,827
Corporate Bonds [Member] | Maximum [Member] | Fixed Maturity Securities [Member] | Liquidity/Duration Adjustment [Member]
Liabilities Fair Value Disclosure [Abstract]
Fixed maturity AFS and trading securities, measurement input	0.240
Corporate Bonds [Member] | Minimum [Member] | Fixed Maturity Securities [Member] | Liquidity/Duration Adjustment [Member]
Liabilities Fair Value Disclosure [Abstract]
Fixed maturity AFS and trading securities, measurement input	0.004
ABS [Member] | Fixed Maturity Securities [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure | $	$ 24
ABS [Member] | Maximum [Member] | Fixed Maturity Securities [Member] | Liquidity/Duration Adjustment [Member]
Liabilities Fair Value Disclosure [Abstract]
Fixed maturity AFS and trading securities, measurement input	0.030
ABS [Member] | Minimum [Member] | Fixed Maturity Securities [Member] | Liquidity/Duration Adjustment [Member]
Liabilities Fair Value Disclosure [Abstract]
Fixed maturity AFS and trading securities, measurement input	0.030
Foreign Government Bonds [Member] | Fixed Maturity Securities [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure | $	$ 76
Foreign Government Bonds [Member] | Maximum [Member] | Fixed Maturity Securities [Member] | Liquidity/Duration Adjustment [Member]
Liabilities Fair Value Disclosure [Abstract]
Fixed maturity AFS and trading securities, measurement input	0.038
Foreign Government Bonds [Member] | Minimum [Member] | Fixed Maturity Securities [Member] | Liquidity/Duration Adjustment [Member]
Liabilities Fair Value Disclosure [Abstract]
Fixed maturity AFS and trading securities, measurement input	0.011
Hybrid And Redeemable Preferred Securities [Member] | Fixed Maturity Securities [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure | $	$ 4
Hybrid And Redeemable Preferred Securities [Member] | Maximum [Member] | Fixed Maturity Securities [Member] | Liquidity/Duration Adjustment [Member]
Liabilities Fair Value Disclosure [Abstract]
Fixed maturity AFS and trading securities, measurement input	0.015
Hybrid And Redeemable Preferred Securities [Member] | Minimum [Member] | Fixed Maturity Securities [Member] | Liquidity/Duration Adjustment [Member]
Liabilities Fair Value Disclosure [Abstract]
Fixed maturity AFS and trading securities, measurement input	0.015
Equity Securities [Member] | Fixed Maturity Securities [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure | $	$ 21
Equity Securities [Member] | Maximum [Member] | Fixed Maturity Securities [Member] | Liquidity/Duration Adjustment [Member]
Liabilities Fair Value Disclosure [Abstract]
Equity securities, measurement input	0.052
Equity Securities [Member] | Minimum [Member] | Fixed Maturity Securities [Member] | Liquidity/Duration Adjustment [Member]
Liabilities Fair Value Disclosure [Abstract]
Equity securities, measurement input	0.045
GLB Ceded Embedded Derivatives [Member] | Other Assets [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure | $	$ 844
GLB Ceded Embedded Derivatives [Member] | Maximum [Member] | Other Assets [Member] | Lapse Rate [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	0.30
GLB Ceded Embedded Derivatives [Member] | Minimum [Member] | Other Assets [Member] | Lapse Rate [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	0.01
GLB Embedded Derivative [Member] | Maximum [Member] | Other Assets [Member] | Utilization Of Guaranteed Withdrawls [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	1
GLB Embedded Derivative [Member] | Maximum [Member] | Other Assets [Member] | Claims Utilization Factor [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	1
GLB Embedded Derivative [Member] | Maximum [Member] | Other Assets [Member] | Premiums Utilization Factor [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	1.15
GLB Embedded Derivative [Member] | Maximum [Member] | Other Assets [Member] | NPR [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	0.0035
GLB Embedded Derivative [Member] | Maximum [Member] | Other Assets [Member] | Volatility [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	0.29
GLB Embedded Derivative [Member] | Minimum [Member] | Other Assets [Member] | Utilization Of Guaranteed Withdrawls [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	0.85
GLB Embedded Derivative [Member] | Minimum [Member] | Other Assets [Member] | Claims Utilization Factor [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	0.60
GLB Embedded Derivative [Member] | Minimum [Member] | Other Assets [Member] | Premiums Utilization Factor [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	0.80
GLB Embedded Derivative [Member] | Minimum [Member] | Other Assets [Member] | NPR [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	0.0002
GLB Embedded Derivative [Member] | Minimum [Member] | Other Assets [Member] | Volatility [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	0.01
Indexed Annuity And IUL Contracts [Member] | Other Assets [Member]
Assets Fair Value Disclosure [Abstract]
Assets Fair Value Disclosure | $	$ 891
Indexed Annuity And IUL Contracts [Member] | Maximum [Member] | Other Assets [Member] | Lapse Rate [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	0.09
Indexed Annuity And IUL Contracts [Member] | Minimum [Member] | Other Assets [Member] | Lapse Rate [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative assets, measurement input	0.01
Future contract benefits - indexed annuity and IUL contracts embedded derivatives | Future Contract Benefits [Member]
Liabilities Fair Value Disclosure [Abstract]
Liabilities measured at fair value | $	$ (2,098)
Future contract benefits - indexed annuity and IUL contracts embedded derivatives | Maximum [Member] | Future Contract Benefits [Member] | Lapse Rate [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	0.09
Future contract benefits - indexed annuity and IUL contracts embedded derivatives | Minimum [Member] | Future Contract Benefits [Member] | Lapse Rate [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	0.01
GLB Direct Embedded Derivatives [Member] | Other Liabilities [Member]
Liabilities Fair Value Disclosure [Abstract]
Liabilities measured at fair value | $	$ (846)
GLB Direct Embedded Derivatives [Member] | Maximum [Member] | Other Liabilities [Member] | Lapse Rate [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	0.30
GLB Direct Embedded Derivatives [Member] | Maximum [Member] | Other Liabilities [Member] | Utilization Of Guaranteed Withdrawls [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	1
GLB Direct Embedded Derivatives [Member] | Maximum [Member] | Other Liabilities [Member] | Claims Utilization Factor [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	1
GLB Direct Embedded Derivatives [Member] | Maximum [Member] | Other Liabilities [Member] | Premiums Utilization Factor [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	1.15
GLB Direct Embedded Derivatives [Member] | Maximum [Member] | Other Liabilities [Member] | NPR [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	0.0035
GLB Direct Embedded Derivatives [Member] | Maximum [Member] | Other Liabilities [Member] | Volatility [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	0.29
GLB Direct Embedded Derivatives [Member] | Minimum [Member] | Other Liabilities [Member] | Lapse Rate [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	0.01
GLB Direct Embedded Derivatives [Member] | Minimum [Member] | Other Liabilities [Member] | Utilization Of Guaranteed Withdrawls [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	0.85
GLB Direct Embedded Derivatives [Member] | Minimum [Member] | Other Liabilities [Member] | Claims Utilization Factor [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	0.60
GLB Direct Embedded Derivatives [Member] | Minimum [Member] | Other Liabilities [Member] | Premiums Utilization Factor [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	0.80
GLB Direct Embedded Derivatives [Member] | Minimum [Member] | Other Liabilities [Member] | NPR [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	0.0002
GLB Direct Embedded Derivatives [Member] | Minimum [Member] | Other Liabilities [Member] | Volatility [Member]
Liabilities Fair Value Disclosure [Abstract]
Derivative liability, measurement input	0.01