Changes in Plan Assets and Benefit Obligation Recognized in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Pension liability in other comprehensive income, beginning of year	$ (4,359)	$ (1,495)
Plan change	495
Net gain	(18)	(3,014)
Amortization of prior service cost	329	150
Pension liability in other comprehensive income, end of year	$ (3,553)	$ (4,359)