Income Tax Effects Allocated to and Cumulative Balance of Accumulated Other Comprehensive Income (loss) (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2015 USD ($)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ (11,926)
Pretax Amount	(15,113)
Tax Effect	125
Net-of-Tax Amount	(15,238)
Ending Balance	(27,164)
Foreign currency translation adjustments and transfers from noncontrolling interests
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(13,564)
Pretax Amount	(17,150)
Tax Effect	(622)
Net-of-Tax Amount	(16,528)
Ending Balance	(30,092)
Unrealized gain on available-for-sale securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	1,105
Pretax Amount	1,346
Tax Effect	497
Net-of-Tax Amount	849
Ending Balance	1,954
Change in AOCI related to postretirement healthcare plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	533
Pretax Amount	691
Tax Effect	250
Net-of-Tax Amount	441
Ending Balance	$ 974