Consolidation of Variable Interest Entities - Additional Information (Detail) $ in Thousands	Sep. 30, 2015 USD ($) Contract	Dec. 31, 2014 USD ($) Contract
Variable Interest Entity [Line Items]
Number of policies owned (contracts) | Contract	634	607
Life insurance policies with aggregate death benefit	$ 2,997,903	$ 2,931,066
Life insurance estimated fair value	$ 457,810	$ 388,886
White Eagle | Revolving Credit Facility | Securities Pledged as Collateral
Variable Interest Entity [Line Items]
Number of policies owned (contracts) | Contract	439
Life insurance policies with aggregate death benefit	$ 2,200,000
Life insurance estimated fair value	$ 327,400
Red Falcon | Revolving Credit Facility | Securities Pledged as Collateral
Variable Interest Entity [Line Items]
Number of policies owned (contracts) | Contract	157
Life insurance policies with aggregate death benefit	$ 604,800
Life insurance estimated fair value	$ 117,400