Other Assets, Net - Other Assets, Net (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred financing costs - noncurrent	$ 138.5	$ 35.5
Equity method investments	124.9us-gaap_EquityMethodInvestments	102.0us-gaap_EquityMethodInvestments
Derivative assets - noncurrent	164.8us-gaap_DerivativeAssetsNoncurrent	174.1us-gaap_DerivativeAssetsNoncurrent
Other assets	102.2us-gaap_OtherAssets	51.9us-gaap_OtherAssets
Other assets, net	$ 530.4us-gaap_OtherAssetsNoncurrent	$ 363.5us-gaap_OtherAssetsNoncurrent

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Net amount of long-term deferred finance costs capitalized at the end of the reporting period.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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The aggregate carrying amounts, as of the balance sheet date, of assets not separately disclosed in the balance sheet.

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Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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