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Represents minimum taxable income required to be generated for full realization of deferred tax asset.

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Represents minimum percentage of change in ownership for annual limitation on utilization of loss carryforwards and credit carryforwards over a period.

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No definition available.

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Represents period of change in ownership percentage for annual limitation on utilization of loss carryforwards and credit carryforwards.

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No definition available.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws that are not subject to expiration.

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No definition available.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws that are subject to expiration over the five year period following the balance sheet date.

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No definition available.

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Period in which foreign tax credit carryforwards may be realized, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign tax credit carryforwards.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Income Taxes (Details 6) (USD $)	12 Months Ended	3 Months Ended		12 Months Ended
Income Taxes (Details 6) (USD $)	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2013
Operating loss carryforwards
Foreign tax credit carryforwards available to offset future payments	$ 136,864,000	$ 136,864,000	$ 124,850,000	$ 124,850,000
Alternative minimum tax credit carryforwards available to offset future payments	5,685,000	5,685,000	5,615,000	5,615,000
Income taxes
Change in ownership percentage, minimum	50.00%
Period of ownership percentage change	3 years
U.S. federal
Operating loss carryforwards
Net operating loss carryforward	93,300,000	93,300,000
Income taxes
Valuation allowance recorded against deferred tax asset		7,200,000
Foreign tax credit carryforward period	10 years
Foreign
Operating loss carryforwards
Net operating loss carryforward	360,000,000	360,000,000
Net operating loss carryforwards, not subject to expiration	205,400,000	205,400,000
Net operating loss carryforwards, subject to expiration	44,100,000	44,100,000
Income taxes
Cumulative earnings generated by non-U.S. subsidiaries	705,400,000	705,400,000
Foreign \| Italy
Income taxes
Valuation allowance recorded against deferred tax asset			9,000,000
Minimum taxable income for realization of deferred tax asset				$ 40,000,000