Derivative Instruments - Fair Values of Derivatives, Balance Sheet Classification (Detail) (Other Assets, Net, USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Derivatives, Fair Value [Line Items]
Derivatives	$ 4,043	$ 3,964
Warrants
Derivatives, Fair Value [Line Items]
Derivatives	$ 4,043	$ 3,964

Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments which are expected to exist longer than one year or beyond the normal operating cycle, if longer, net of the effects of master netting arrangements.

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+ Details