Investment Securities - Schedule of Amortized Cost and Estimated Fair Value of Fixed-Maturity Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Maturity in:
Amortized Cost, 2015	$ 71,576
Amortized Cost, 2016-2019	35,612
Total fixed-maturity securities, Amortized Cost	107,188	$ 60,202
Estimated Fair Value, 2015	71,595
Estimated Fair Value, 2016-2019	35,749
Total fixed-maturity securities, Estimated Fair Value	$ 107,344	$ 60,641

Fixed maturity securities amortized cost.

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Fixed maturity securities debt maturities after through five years amortized cost.

No definition available.

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Fixed maturity securities debt maturities after one through five years fair value.

No definition available.

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Fixed maturity securities debt maturities within one year amortized cost.

No definition available.

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Fixed maturity securities debt maturities within one year fair value.

No definition available.

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Fixed maturity securities estimated fair value.

No definition available.

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Schedule of Amortized cost and estimated fair value of fixed-maturity securities by contractual maturity.

No definition available.

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