Other Comprehensive Income (Loss) (Components of Other Comprehensive Income (Loss)) (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Components of Other Comprehensive Income (Loss) [Line Items]
Foreign currency translation adjustment, gross	$ 35,455	$ 84,500	$ (67,349)	$ 155,153
Other comprehensive income (loss), gross total	39,082	90,698	(50,805)	158,903
Foreign currency translation adjustment, tax
Income tax (benefit) expense related to items of other comprehensive income loss	(985)	(4,016)	(4,405)	(1,123)
Amounts reclassified, net of tax			(1,721)	3,433
Changes in fair value, net of tax			13,860	(806)
Foreign currency translation adjustment, net	35,455	84,500	(67,349)	155,153
Other comprehensive income (loss), total, net of tax	38,097	86,682	(55,210)	157,780
Interest Rate Swap [Member]
Components of Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified, gross	4,279	511	2,407	2,352
Changes in fair value, gross	863	2,181	15,828	305
Amounts reclassified, tax effect	(1,134)	(135)	(638)	(623)
Changes in fair value, tax effect	(229)	(2,542)	(4,194)	(81)
Amounts reclassified, net of tax	3,145	376	1,769	1,729
Changes in fair value, net of tax	634	(361)	11,634	224
Fuel [Member] \| Commodity Contract [Member]
Components of Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified, gross	(1,810)	789	(4,647)	2,765
Changes in fair value, gross	295	2,717	2,956	(1,672)
Amounts reclassified, tax effect	451	(302)	1,157	(1,061)
Changes in fair value, tax effect	(73)	(1,037)	(730)	642
Amounts reclassified, net of tax	(1,359)	487	(3,490)	1,704
Changes in fair value, net of tax	$ 222	$ 1,680	$ 2,226	$ (1,030)

Amount before tax, after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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