Dispositions - Separation of Brighthouse - Ongoing Reinsurance Transactions (Effects of Reinsurance on Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets
Premiums and Other Receivables, Net	$ 19,644	$ 18,423
Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Net	18,895	18,419	$ 17,590
Total assets	38,539	36,842
Liabilities
Future policy benefits	186,780	177,974
Policyholder account balances	183,693	182,518
Other policy-related balances	16,529	15,515
Other Liabilities	22,964	23,982
Total liabilities	409,966	399,989
Direct
Assets
Premiums and Other Receivables, Net	5,988	6,300
Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Net	18,812	18,350
Total assets	24,800	24,650
Liabilities
Future policy benefits	183,367	174,694
Policyholder account balances	183,207	182,226
Other policy-related balances	15,519	14,962
Other Liabilities	14,848	17,077
Total liabilities	396,941	388,959
Assumed
Assets
Premiums and Other Receivables, Net	1,603	866
Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Net	385	398
Total assets	1,988	1,264
Liabilities
Future policy benefits	3,413	3,280
Policyholder account balances	488	293
Other policy-related balances	986	520
Other Liabilities	2,131	1,896
Total liabilities	7,018	5,989
Ceded
Assets
Premiums and Other Receivables, Net	12,053	11,257
Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Net	(302)	(329)
Total assets	11,751	10,928
Liabilities
Future policy benefits	0	0
Policyholder account balances	(2)	(1)
Other policy-related balances	24	33
Other Liabilities	5,985	5,009
Total liabilities	$ 6,007	5,041
Affiliated Entity [Member] | Assumed
Assets
Premiums and Other Receivables, Net		167
Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Net		384
Total assets		551
Liabilities
Future policy benefits		1,734
Other policy-related balances		119
Other Liabilities		1,458
Total liabilities		3,311
Affiliated Entity [Member] | Ceded
Assets
Premiums and Other Receivables, Net		1,793
Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Net		(40)
Total assets		1,753
Liabilities
Future policy benefits		0
Other policy-related balances		28
Other Liabilities		19
Total liabilities		$ 47