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Income Taxes (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 | Jul. 28, 2011 Tax Assessment Year 2007 to 2009 Internal Revenue Service (IRS)
Income Tax Contingency [Line Items] |  |  |  |  |
Effective tax rates (as a percent) | (16.70%) | 17.00% | 26.40% | 21.00% |
U.S. statutory rate (as a percent) |  | 35.00% | 35.00% | 35.00% |
Foreign tax credit carryforwards | $ 18.7 |  | $ 18.7 |  |
Total tax assessment |  |  |  |  | 87.4
Tax assessments related to disallowed deductions |  |  |  |  | $ 80.6

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