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Derivative Financial Instruments (Textuals) (Details) € in Millions, ¥ in Millions, SGD in Millions, $ in Millions | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2017 USD ($) | Dec. 31, 2017 EUR (€) MBbls | Dec. 31, 2017 JPY (¥) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2017 SGD MBbls | Dec. 31, 2017 USD ($) MBbls | Oct. 02, 2017 USD ($) | Dec. 31, 2016 EUR (€) MBbls | Dec. 31, 2016 USD ($) MBbls
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  | $ 197.0 |  |  | $ 228.6
Forward-Start Interest Rate Swap [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  |  | $ 33.1 |  | $ 34.9
Debt Instrument, Description of Variable Rate Basis |  | one-month LIBOR | one-month LIBOR | one-month LIBOR |  |  |  |  |  |
Maximum term (in years) |  | 5 years | 5 years | 5 years |  |  |  |  |  |
Fixed interest rate |  | 5.41% |  |  |  | 5.41% | 5.41% |  |  |
Euro Note B [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative foreign currency translation loss |  |  |  |  |  |  | $ 1.3 |  |  |
Cumulative foreign currency translation loss, net of tax |  |  |  |  |  |  | 1.2 |  |  |
Euro-Denominated Revolver [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount, nonderivative instruments |  | € 21.0 |  | $ 25.2 |  |  |  |  |  |
Debt Yen Denominated [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount, nonderivative instruments |  |  | ¥ 500.0 | 4.4 |  |  |  |  |  |
Cumulative foreign currency translation loss |  |  |  |  |  |  | 0.3 |  |  |
Cumulative foreign currency translation loss, net of tax |  |  |  |  |  |  | $ 0.2 |  |  |
Commodity Call Options [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Purchased call options, barrels of crude oil (in barrels) | MBbls |  | 125,166 |  |  |  | 125,166 | 125,166 |  | 96,525 | 96,525
Gain (loss) recorded in cost of goods and services sold, call options | $ 0.1 |  |  | $ 0.2 | $ 0.1 |  |  |  |  |
Commodity Call Options Held [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Purchased call options, barrels of crude oil (in barrels) | MBbls |  | 115,701 |  |  |  | 115,701 | 115,701 |  |  |
Euro Member Countries, Euro | Forward Contracts [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount | € |  | € 12.0 |  |  |  |  |  |  | € 57.5 |
United States of America, Dollars | Forward Contracts [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  | $ 13.4 |  |  |
United States of America, Dollars | Long [Member] | Foreign Exchange Forward [Member] | Designated as Hedging Instrument [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  | 39.0 |  |  |
United States of America, Dollars | Short [Member] | Foreign Exchange Forward [Member] | Designated as Hedging Instrument [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount |  | 34.4 |  |  |  |  | 0.0 |  |  |
Japan, Yen | Long [Member] | Foreign Exchange Forward [Member] | Designated as Hedging Instrument [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  | 5,157.3 |  |  |
Japan, Yen | Short [Member] | Foreign Exchange Forward [Member] | Designated as Hedging Instrument [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount |  | 19.8 |  |  |  |  | 23.5 |  |  |
Singapore, Dollars | Forward Contracts [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount | SGD |  |  |  |  |  | SGD 171.0 |  |  |  |
Singapore, Dollars | Long [Member] | Foreign Exchange Forward [Member] | Designated as Hedging Instrument [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  | 35.2 |  |  |
Singapore, Dollars | Short [Member] | Foreign Exchange Forward [Member] | Designated as Hedging Instrument [Member] |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount |  | € 6.9 |  |  |  |  | $ 17.7 |  |  |

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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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