Employee Benefit Plans - Changes in Plan Assets and Benefit Obligations in Other Comprehensive Income (loss) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Pension Benefit Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net actuarial (loss) gain	$ (35)	$ (92)	$ 298
Settlement losses	414	50	52
Plan amendment and curtailment	0	0	0
Recognized net actuarial loss	25	20	66
Amortization of prior service cost	0	0	0
Recognition of prior service cost due to curtailments	0	0	0
Total other comprehensive income (loss), pre-tax	404	(22)	416
Income tax expense (benefit)	160	(155)	166
Total other comprehensive income (loss), net of tax	244	133	250
Post-Employment Benefit Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net actuarial (loss) gain	(35)	(1,632)	558
Settlement losses	0	0	0
Plan amendment and curtailment	0	1,183	0
Recognized net actuarial loss	278	18	28
Amortization of prior service cost	(338)	(369)	(647)
Recognition of prior service cost due to curtailments	0	(52)	0
Total other comprehensive income (loss), pre-tax	(95)	(852)	(61)
Income tax expense (benefit)	(41)	(6)	(22)
Total other comprehensive income (loss), net of tax	$ (54)	$ (846)	$ (39)