Summary of Significant Accounting Policies - Schedule of Life Settlement Contracts Fair Value Method (Detail) $ in Millions	Dec. 31, 2015 USD ($) Contract
Accounting Policies [Abstract]
Number of Life Settlement Contracts 2016 \| Contract	60
Number of Life Settlement Contracts 2017 \| Contract	60
Number of Life Settlement Contracts 2018 \| Contract	50
Number of Life Settlement Contracts 2019 \| Contract	40
Number of Life Settlement Contracts 2020 \| Contract	40
Number of Life Settlement Contracts Thereafter \| Contract	300
Number of Life Settlement Contracts Total \| Contract	550
Fair Value of Life Settlement Contracts 2016	$ 11
Fair Value of Life Settlement Contracts 2017	10
Fair Value of Life Settlement Contracts 2018	8
Fair Value of Life Settlement Contracts 2019	6
Fair Value of Life Settlement Contracts 2020	5
Thereafter Fair Value of Life Settlement Contracts Thereafter	34
Fair Value of Life Settlement Contracts Total	74
Face Amount of Life Insurance Policies 2016	35
Face Amount of Life Insurance Policies 2017	31
Face Amount of Life Insurance Policies 2018	27
Face Amount of Life Insurance Policies 2019	24
Face Amount of Life Insurance Policies 2020	21
Face Amount of Life Insurance Policies Thereafter	167
Face Amount of Life Insurance Policies Total	$ 305

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Face value (death benefits) of the life insurance policies underlying the life settlement contracts accounted for under the fair value method.

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