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Income Taxes - Major Jurisdictions (Detail) | 12 Months Ended
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Dec. 31, 2014
United States [Member] |
Income Tax Contingency [Line Items] |
Tax Year | 2010
New York State [Member] |
Income Tax Contingency [Line Items] |
Tax Year | 2010
New York City [Member] |
Income Tax Contingency [Line Items] |
Tax Year | 2011
United Kingdom [Member] |
Income Tax Contingency [Line Items] |
Tax Year | 2009
Italy [Member] |
Income Tax Contingency [Line Items] |
Tax Year | 2009

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