Other Comprehensive Income - Comprehensive Income (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Equity [Abstract]
Net income	$ 161,010us-gaap_ProfitLoss	$ 157,484us-gaap_ProfitLoss
Other comprehensive (loss) income:
Foreign currency translation	(113,309)	102
Pension and other post-retirement benefit adjustments:
Recognition of prior service credit, net of tax	(240)	(487)
Recognition of actuarial loss, net of tax	6,078	4,278
Net current period other comprehensive income (loss)	(107,471)	3,893
Comprehensive income	$ 53,539	$ 161,377

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

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Amount after tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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