Accumulated Other Comprehensive (loss) Income - Components of Accumulated Other Comprehensive (Loss) Income (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Beginning Balance, Gains and Losses on Hedging Derivatives
Other comprehensive income (loss) before reclassifications, Gains and Losses on Hedging Derivatives	(8,542)		(2,264)
Amounts reclassified from accumulated other comprehensive (loss) income into earnings, Gains and Losses on Hedging Derivatives	542		42,515
Net current-period other comprehensive (loss) income, Gains and Losses on Hedging Derivatives	(8,000)
Ending Balance, Gains and Losses on Hedging Derivatives	(8,000)
Beginning Balance, Foreign Currency Gain (Loss)	(7,438)	46,181
Other comprehensive income (loss) before reclassifications, Foreign Currency Gain (Loss)	(141,530)	(53,619)
Amounts reclassified from accumulated other comprehensive (loss) income into earnings, Foreign Currency Gain (Loss)	0	0
Net current-period other comprehensive (loss) income, Foreign Currency Gain (Loss)	(141,530)	(53,619)	58,626
Ending Balance, Foreign Currency Gain (Loss)	(148,968)	(7,438)	46,181
Beginning Balance, Adjustment to Early Retiree Medical Plan	16,518	10,580
Other comprehensive income (loss) before reclassifications, Adjustment to Early Retiree Medical Plan	(4,228)	5,938	(3,646)
Amounts reclassified from accumulated other comprehensive (loss) income into earnings, Adjustment to Early Retiree Medical Plan	(1,030)
Net current-period other comprehensive (loss) income, Adjustment to Early Retiree Medical Plan	(5,258)	5,938
Ending Balance, Adjustment to Early Retiree Medical Plan	11,260	16,518	10,580
Beginning Balance	9,080	56,761
Other comprehensive income (loss) before reclassifications	(154,300)	(47,681)
Amounts reclassified from accumulated other comprehensive (loss) income into earnings	(488)
Net current-period other comprehensive (loss) income	(154,788)	(47,681)	95,231
Ending Balance	$ (145,708)	$ 9,080	$ 56,761

Net of tax amount reclassified from accumulated other comprehensive (loss) income into earnings.

No definition available.

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- Definition

Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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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.

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

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Amount after tax and 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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Amount after tax and 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.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for translation gain (loss) realized upon the sale or liquidation of an investment in a foreign entity and foreign currency hedges that are designated and qualified as hedging instruments for hedges of the foreign currency exposure of a net investment in a foreign operation.

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

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Amount after tax, before reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement benefit plans.

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (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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Amount after tax 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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