Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis Narrative (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Valuation allowance	$ 919	$ 1,631
Reported Value Measurement [Member] | Fair Value, Measurements, Nonrecurring [Member]
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Valuation allowance	$ 900	$ 1,600