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Derivative Instruments (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Dec. 31, 2014
Derivative [Line Items] |  |  |  |
Intercompany debt designated as a non-derivative net investment hedging instrument | $ 13.2 |  | $ 13.2 | $ 15.8
Gain (loss) currency translation adjustment | $ 1.8 | $ 0.7 |  |
Foreign Currency Derivatives |  |  |  |
Derivative [Line Items] |  |  |  |
Notional amounts of foreign currency derivatives |  |  |  | $ 20.0
Minimum | Foreign Currency Derivatives |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative maturities |  |  | November 2015 |
Maximum | Foreign Currency Derivatives |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative maturities |  |  | December 2015 |

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- Definition Derivative maturities + References No definition available. + Details
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Amount of gain (loss) from the ineffectiveness of the hedge. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986 + Details
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- Definition Net fair value of all derivatives designated as hedges of net investment in foreign operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 + Details
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