Defined Contribution Plans, Pension and Other Post-Retirement Benefit Plans - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Recognized expense associated with defined contribution plans	$ 2,800	$ 2,200	$ 2,200
Expected contribution to pension plans and post-retirement benefit plans	$ 3,000
Maturity period of investments	90 days
Annual rate of increase in per capital cost for 2014	6.00%
Rate of assumed decrease in per capital cost through 2018	5.00%
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Actuarial loss (gain)	$ 500
Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Actuarial loss (gain)	4	$ (113)
Amortization of other comprehensive income into net periodic benefit cost	$ 100