Fair Value of Financial Instruments - Estimated Fair Value of the Embedded Derivative (Detail) - Senior Subordinated Notes - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
2018 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated fair value of the embedded derivative	$ 11	$ 35
2019 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated fair value of the embedded derivative	$ 45	$ 48

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Balance Type:	credit
Period Type:	instant