Average notional amount specified by the derivative(s). Expressed as an absolute value.

No definition available.

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- Definition

The estimated value of gains (losses), net anticipated to be transferred in the next twelve months from accumulated other comprehensive income into earnings.

+ References

No definition available.

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- Definition

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

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- Definition

The aggregate fair value of assets needed to immediately settle the derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

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- Definition

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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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

No definition available.

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- Definition

Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

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- Definition

Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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Derivative Financial Instruments - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Derivative financial instruments
Aggregate fair value of derivative instruments with credit-risk-related contingent features, in case of net liability position	$ 138,689		$ 93,761
Collateral under derivative counterparty collateral agreements	107,344		42,750
Fair value of assets required to settle the derivatives in, net liability position	21,449
Additional collateral to satisfy collateral netting arrangements	128,868		52,330
Unrestricted cash collateral pledged	637		4,911
Net derivative gains estimated to be reclassified from accumulated other comprehensive income (loss) into net income within the next twelve months	62,494
Net investment income
Derivative financial instruments
Change in fair value of GLWB	7,102	$ 1,670
Policyholders' Funds
Derivative financial instruments
Embedded derivatives - GLWB	3,993		11,095
Interest rate swaps
Derivative financial instruments
Average notional amount of the derivative instruments	747,900		905,977
Cross-currency swaps
Derivative financial instruments
Average notional amount of the derivative instruments	1,461,328		1,323,398
Future
Derivative financial instruments
Average notional amount of the derivative instruments	89,085		108,438
Swaption
Derivative financial instruments
Average notional amount of the derivative instruments	170,701		162,896
Other forward contracts
Derivative financial instruments
Average notional amount of the derivative instruments	1,652,500		2,231,196
Other counterparties
Derivative financial instruments
Unrestricted cash collateral pledged	637		5,490
Pledged collateral
Derivative financial instruments
Collateral under derivative counterparty collateral agreements	$ 117,240		$ 42,750