Variable Annuity and Insurance Guarantees (VA Guarantees Details Text) (Details) - GMAB [Member]	12 Months Ended
Dec. 31, 2017
Variable Annuity Guarantees by Benefit Type
Maximum age of variable annuity contractholders	79 years
GMAB rider guarantees waiting period	10 years

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.

No definition available.

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