Reserve for Future Policy Benefits and Separate Account Liabilities Level 4 Changes in Reserve for Future Policy Benefits (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable	$ 4,756,000,000	$ 4,659,000,000
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable, Incurred Benefits, Net	534,000,000	258,000,000
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverables, Payment for Benefits, Net	144,000,000	161,000,000
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable	5,146,000,000	4,756,000,000
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	14,000,000,000	13,850,000,000
Liabilities for Guarantees on Long-Duration Contracts, Incurred Benefits	1,275,000,000	1,022,000,000
Liabilities for Guarantees on Long-Duration Contracts, Payment for Benefits	885,000,000	899,000,000
Liabilities for Guarantees on Long-Duration Contracts, Other Liability Adjustments	(92,000,000)	(27,000,000)
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	14,482,000,000	14,000,000,000
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross, HLIC ceded to HLA	285
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable	288,000,000
Guaranteed Minimum Death Benefit [Member]
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable	432,000,000	523,000,000
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable, Incurred Benefits, Net	113,000,000	0
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverables, Payment for Benefits, Net	81,000,000	91,000,000
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable	464,000,000	432,000,000
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	786,000,000	863,000,000
Liabilities for Guarantees on Long-Duration Contracts, Incurred Benefits	185,000,000	37,000,000
Liabilities for Guarantees on Long-Duration Contracts, Payment for Benefits	98,000,000	114,000,000
Liabilities for Guarantees on Long-Duration Contracts, Other Liability Adjustments	0	0
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	873,000,000	786,000,000
Secondary Guarantees [Member] | Universal Life [Member]
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable	2,627,000,000	2,313,000,000
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable, Incurred Benefits, Net	313,000,000	314,000,000
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable	2,940,000,000	2,627,000,000
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	2,627,000,000	2,313,000,000
Liabilities for Guarantees on Long-Duration Contracts, Incurred Benefits	313,000,000	314,000,000
Liabilities for Guarantees on Long-Duration Contracts, Other Liability Adjustments	0	0
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	2,940,000,000	2,627,000,000
Annuitization Benefit [Member]
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable	1,697,000,000	1,823,000,000
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable, Incurred Benefits, Net	108,000,000	(56,000,000)
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverables, Payment for Benefits, Net	63,000,000	70,000,000
Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable	1,742,000,000	1,697,000,000
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	10,587,000,000	10,674,000,000
Liabilities for Guarantees on Long-Duration Contracts, Incurred Benefits	777,000,000	671,000,000
Liabilities for Guarantees on Long-Duration Contracts, Payment for Benefits	787,000,000	785,000,000
Liabilities for Guarantees on Long-Duration Contracts, Other Liability Adjustments	(92,000,000)	(27,000,000)
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross	$ 10,669,000,000	$ 10,587,000,000