Annual report pursuant to Section 13 and 15(d)

Income Taxes - Summary of Differences between the Financial Statement and Tax Bases of Assets and Liabilities (Detail)

v2.4.1.9
Income Taxes - Summary of Differences between the Financial Statement and Tax Bases of Assets and Liabilities (Detail) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2014
Dec. 31, 2013
Deferred Tax Assets:    
Basis difference in fixed assets $ 63,931us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment $ 31,440us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment
Foreign tax credit carry forward 48,928us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsForeign 55,908us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsForeign
Alternative minimum tax credit carryover 1,349us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax 1,349us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax
Foreign net operating losses 44,228us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsForeign 42,688us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsForeign
Asset retirement obligations 5,196us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAssetRetirementObligations 4,012us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAssetRetirementObligations
Other 3,828us-gaap_DeferredTaxAssetsOther 3,300us-gaap_DeferredTaxAssetsOther
Deferred Tax Assets, Gross 167,460us-gaap_DeferredTaxAssetsGross 138,697us-gaap_DeferredTaxAssetsGross
Valuation allowance (166,111)us-gaap_DeferredTaxAssetsValuationAllowance (137,348)us-gaap_DeferredTaxAssetsValuationAllowance
Total deferred tax asset $ 1,349us-gaap_DeferredTaxAssetsLiabilitiesNet $ 1,349us-gaap_DeferredTaxAssetsLiabilitiesNet