Minimum Guarantees - Assumptions and Methodologies Used to Determine GMDB (Details) - GMDB - Scenario	Dec. 31, 2016	Dec. 31, 2015
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Data used (number of scenarios)	1,050	1,050
Discount rates	5.00%	5.00%
Minimum \| Regular Equity
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Mean investment performance	7.00%	7.00%
Volatility	10.00%	10.00%
Minimum \| Fixed, Bond, Money Market
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Mean investment performance	0.00%	0.00%
Volatility	0.00%	0.00%
Maximum \| Regular Equity
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Mean investment performance	13.00%	13.00%
Volatility	35.00%	35.00%
Maximum \| Fixed, Bond, Money Market
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Mean investment performance	10.00%	10.00%
Volatility	9.00%	9.00%

Long-Duration Contracts, Assumptions by Product and Guarantee, Number of Investment Performance Scenarios

No definition available.

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- Definition

Percentage discount rate used to calculate present value of an expected stream of future payments, which is included in the calculation of the amount of the specified guaranteed benefit obligation as of the balance sheet date.

+ References

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-Publisher FASB
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- Definition

Estimated average rate of return on investments which is included in the calculation of the amount of the specified guaranteed benefit obligation as of the balance sheet date.

+ References

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-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Percentage rate that is indicative of an expected degree of movement against a base line index, and which is included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date.

+ References

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