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Derivative Instruments (Details) - Interest rate contracts $ in Millions | 12 Months Ended
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Dec. 31, 2015 USD ($) item | Dec. 31, 2014 USD ($) item
Derivative instruments |  |
Variable rate of debt | one-month LIBOR | one-month LIBOR
Borrowings at variable interest rates | $ 562.1 | $ 468.5
Number of interest rate swap agreements | item | 0 | 1
Notional amount outstanding |  | $ 100.0
Fixed interest rate (as a percent) |  | 2.10%
(Benefit) expense recorded to net finance costs | $ (0.5) | $ 1.5

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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 The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR. + References No definition available. + Details
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- Definition Fixed interest rate related to the interest rate derivative. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time. + References No definition available. + Details
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- Definition Number of interest rate derivative instruments held by the entity at the reporting date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5579245-113959 + Details
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- Definition Represents the amount of benefit recorded to net finance costs related expired derivative contracts. + References No definition available. + Details
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- Details
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