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Summary of Significant Accounting Policies (Foreign Currency Exchange) (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
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Significant Transactions |  |  |
Net unrealized foreign currency translation (losses) gains | (79.8)us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax | 88.4 us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax |
SEK |  |  |
Significant Transactions |  |  |
Foreign currency exchange rate | 7.7737 us-gaap_ForeignCurrencyExchangeRateTranslation1 / us-gaap_CurrencyAxis = currency_SEK | 6.4339 us-gaap_ForeignCurrencyExchangeRateTranslation1 / us-gaap_CurrencyAxis = currency_SEK | 6.4973 us-gaap_ForeignCurrencyExchangeRateTranslation1 / us-gaap_CurrencyAxis = currency_SEK
GBP |  |  |
Significant Transactions |  |  |
Foreign currency exchange rate | 0.6426 us-gaap_ForeignCurrencyExchangeRateTranslation1 / us-gaap_CurrencyAxis = currency_GBP | 0.6044 us-gaap_ForeignCurrencyExchangeRateTranslation1 / us-gaap_CurrencyAxis = currency_GBP | 0.6154 us-gaap_ForeignCurrencyExchangeRateTranslation1 / us-gaap_CurrencyAxis = currency_GBP
Canada, Dollars |  |  |
Significant Transactions |  |  |
Foreign currency exchange rate | 0.8245 us-gaap_ForeignCurrencyExchangeRateTranslation1 / us-gaap_CurrencyAxis = currency_CAD | 0.7259 us-gaap_ForeignCurrencyExchangeRateTranslation1 / us-gaap_CurrencyAxis = currency_CAD | 0.7564 us-gaap_ForeignCurrencyExchangeRateTranslation1 / us-gaap_CurrencyAxis = currency_CAD

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- Definition Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669686-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e681-108580 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669646-108580 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6915805&loc=d3e32022-110900 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6450520&loc=d3e32583-110901 + Details
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