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Summary of Significant Accounting Policies - Guaranteed Minimum Death Benefit (Details) - Guarantee Minimum Death Benefit - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Net Amount at Risk by Product and Guarantee [Line Items] |  |
GMDB reserve | $ 258 | $ 152
Aggregate in-the-money death benefits under the GMDB provision | $ 48,083 | $ 28,345
Variable annuity contract value distribution based on GMDB feature: |  |
No guarantee | 30.00% | 29.00%
Return of premium guarantee | 65.00% | 65.00%
Guarantee of premium roll-up at an annual rate of 3% or 5% | 5.00% | 6.00%
Total | 100.00% | 100.00%

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- Details
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