Deferred Acquisition Costs, Deferred Sales Inducements, and Value of Business Acquired - Roll Forward of DAC, DSI, and VOBA (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
DAC
Beginning balance	$ 705	$ 424	$ 210
Additions	601	288	250
Unlocking	(12)	(6)	2
Amortization	(114)	(35)	(21)
Impact of unrealized investment (gains) losses	(38)	34	(17)
Ending balance	1,142	705	424
DSI
Beginning balance	320	188	91
Additions	200	136	113
Unlocking	(3)	(2)	6
Amortization	(36)	(19)	(10)
Impact of unrealized investment (gains) losses	(19)	17	(12)
Ending balance	462	320	188
VOBA
Beginning balance	1,627	1,610	1,832
Additions	0	0	0
Unlocking	(23)	(27)	28
Amortization	(169)	(138)	(133)
Impact of unrealized investment (gains) losses	(99)	182	(117)
Ending balance	1,336	1,627	1,610
Total
Beginning balance	2,652	2,222	2,133
Additions	801	424	363
Unlocking	(38)	(35)	36
Amortization	(319)	(192)	(164)
Impact of unrealized investment (gains) losses	(156)	233	(146)
Ending balance	$ 2,940	$ 2,652	$ 2,222

Deferred Policy Acquisition Costs, Deferred Sales Inducements, and Present Value of Future Profits

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Deferred Policy Acquisition Costs, Deferred Sales Inducements, and Present Value of Future Profits, Additions

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Deferred Policy Acquisition Costs, Deferred Sales Inducements, and Present Value of Future Profits, Amortization Expense Excluding Unlocking

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Deferred Policy Acquisition Costs, Deferred Sales Inducements, and Present Value of Future Profits, Amortization Expense Unlocking

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Deferred Policy Acquisition Costs, Deferred Sales Inducements, and Present Value of Future Profits [Roll Forward]

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Deferred Policy Acquisition Costs, Deferred Sales Inducements, and Present Value of Future Profits, Unrealized Investment Gains (Losses)

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Deferred Sales Inducements, Amortization Expense Excluding Unlocking

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Amount of increase (decrease) to amortization expense of deferred sales inducements (DSI) due to assumption change.

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Amount of unrealized investment gain (loss) which decreases (increases) deferred sales inducements.

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Present Value of Future Insurance Profits, Amortization Expense Excluding Unlocking

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Amount of increase (decrease) to amortization expense of value of business acquired (VOBA) due to assumption change.

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Amount of unrealized investment gain (loss) which decreases (increases) value of business acquired.

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Amount of increase (decrease) to amortization expense of deferred policy acquisition cost (DAC) due to assumption change.

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Amount of other increase (decrease) to amortization expense of deferred policy acquisition cost (DAC).

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Amount of unrealized investment gain (loss) which decreases (increases) deferred policy acquisition cost.

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Net amount of deferred policy acquisition costs capitalized on contracts remaining in force as of the balance sheet date.

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Total amount of policy acquisition costs capitalized during the income statement period.

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The amount of deferred sales inducement costs capitalized during the period.

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The unamortized carrying amount of deferred sales inducement costs as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Additions in present value of future profits asset during the year arising from acquisitions of insurance entities.

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The remaining unamortized carrying amount as of the balance sheet date of expected future earnings from insurance contracts acquired (also known as present value of future profits).

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