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Reinsurance Reinsurance (Reinsurance Related Party Narrative) (Details) - USD ($) $ in Millions		1 Months Ended	6 Months Ended	12 Months Ended
	Apr. 30, 2017	Jan. 31, 2017	Jun. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	May 01, 2017	Jan. 01, 2017
Effects of Reinsurance [Line Items]
Premiums and Other Receivables, Net				$ 14,760	$ 13,697
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest				(1,052)	989	$ (615)
Other Liabilities				5,236	4,285
Liability for Future Policy Benefit, after Reinsurance				39,686	36,209
Policyholder Contract Deposit				$ 45,771	40,054
Affiliated Entity \| Life and Other [Member]
Effects of Reinsurance [Line Items]
Premiums and Other Receivables, Net							$ 189
Cash, Cash Equivalents, and Short-term Investments							$ 214
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	$ 17
Affiliated Entity \| Ceded Guaranteed Minimum Benefit [Member]
Effects of Reinsurance [Line Items]
Embedded Derivative, Gain (Loss) on Embedded Derivative, Net					$ (1)	(263)
Affiliated Entity \| Affiliate Recapture Variable Annuities [Member]
Effects of Reinsurance [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest		$ 178
Other Liabilities								$ 274
Affiliated Entity \| Assumed Guaranteed Minimum Benefit [Member]
Effects of Reinsurance [Line Items]
Embedded Derivative, Gain (Loss) on Embedded Derivative, Net						$ 110
Metropolitan Life Insurance Company [Member] \| Affiliated Entity \| BHL Recapture GMIB [Member]
Effects of Reinsurance [Line Items]
Premiums and Other Receivables, Net								140
Cash, Cash Equivalents, and Short-term Investments								568
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest			$ 89
Liability for Future Policy Benefit, after Reinsurance								106
Policyholder Contract Deposit								$ 460