Fair Value Measurements - Fair Value Measurements on a Recurring and Non-Recurring Basis (Detail) (Recurring Basis [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Fair value measurements on a recurring and non-recurring basis
Contingent Liability	$ (477)	$ (477)
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value measurements on a recurring and non-recurring basis
Contingent Liability	0	0
Significant Other Observable Inputs (Level 2) [Member]
Fair value measurements on a recurring and non-recurring basis
Contingent Liability	0	0
Significant Unobservable Inputs (Level 3) [Member]
Fair value measurements on a recurring and non-recurring basis
Contingent Liability	$ (477)	$ (477)