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Income Taxes (Details Textual) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Oct. 31, 2011 | Jun. 30, 2015 | Jun. 30, 2014 | Jun. 30, 2015 | Jun. 30, 2014 | Mar. 31, 2015
Income Tax Contingency [Line Items] |  |  |  |  |  |
Effective tax rate |  | 23.90% | 27.00% | 24.70% | 26.90% |
Notice of assessment of corporate withholding tax including penalties and interest |  |  |  |  |  | $ 48.3
Net benefit for a previously unrecognized position |  | $ 24.0 |  | $ 24.0 |  |
Tax Year 2007 |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |
Proposed deduction disallowance by tax authorities | $ 130.0 |  |  |  |  |
Tax Year 2008 |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |
Proposed deduction disallowance by tax authorities | 130.0 |  |  |  |  |
Tax Year 2009 |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |
Proposed deduction disallowance by tax authorities | $ 130.0 |  |  |  |  |

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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(2)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319 + Details
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- Definition The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
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