Income Taxes - Summary of Deferred Taxes (Detail) $ in Thousands	Sep. 30, 2017 USD ($)
Deferred tax assets:
Reserves for expected costs of liquidation and Residual Wind-Down Claims and Costs	$ 8,979
Net operating and capital loss carryovers	62,561
Gross deferred tax assets	71,540
Less: Valuation allowance	(68,381)
Deferred tax asset, net of valuation allowance	3,159
Deferred tax liabilities:
Accrued investment and other income	(3,159)
Gross deferred tax liabilities	(3,159)
Net deferred taxes	$ 0