Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

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

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Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
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The average strike price on the group of price risk option contracts such as put options or call options.

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Nominal or face amount used to calculate payments on a nonderivative instrument.

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Amount, after tax, of cumulative translation adjustment attributable to gain (loss) on foreign currency derivatives that are designated as, and are effective as, economic hedges of a net investment in a foreign entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 20
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109240241&loc=d3e32211-110900

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Pre-tax cumulative adjustment resulting from gains and losses on foreign currency derivatives that are designated as, and are effective as, hedges of a net investment in a foreign entity, commencing as of the designation date. Adjustment reported in equity as part of accumulated other comprehensive income.

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Derivative Financial Instruments (Textuals) (Details) € in Millions, ¥ in Millions, $ in Millions, $ in Millions	6 Months Ended
	Jun. 30, 2019 EUR (€) MBbls $ / bbl	Jun. 30, 2019 JPY (¥)	Jun. 30, 2019 USD ($)	Jun. 30, 2019 SGD ($) MBbls $ / bbl	Jun. 30, 2019 JPY (¥) MBbls $ / bbl	Jun. 30, 2019 USD ($) MBbls $ / bbl	Dec. 31, 2018 EUR (€)	Dec. 31, 2018 SGD ($)	Dec. 31, 2018 USD ($)	Nov. 22, 2017 MBbls
Debt EUR Denominated [Member]
Derivative [Line Items]
Notional amount, nonderivative instruments	€ 21.0		$ 23.9
Cumulative foreign currency translation loss						$ 0.4
Cumulative foreign currency translation loss, net of tax						0.3
Debt Yen Denominated [Member]
Derivative [Line Items]
Notional amount, nonderivative instruments		¥ 500.0	$ 4.6
Cumulative foreign currency translation loss						0.5
Cumulative foreign currency translation loss, net of tax						$ 0.4
Options Held [Member]
Derivative [Line Items]
Derivative, nonmonetary notional amount \| MBbls	105,891			105,891	105,891	105,891				262,269
Derivative, Average Price Risk Option Strike Price \| $ / bbl	64.02			64.02	64.02	64.02
Euro Member Countries, Euro \| Forward Contracts [Member]
Derivative [Line Items]
Notional amount \| €							€ 10.0
Singapore, Dollars \| Forward Contracts [Member]
Derivative [Line Items]
Notional amount				$ 601.5				$ 601.5
United States of America, Dollars \| Forward Contracts [Member]
Derivative [Line Items]
Notional amount						$ 13.4			$ 13.4
Long [Member] \| Designated as Hedging Instrument [Member] \| Singapore, Dollars \| Foreign Exchange Forward [Member]
Derivative [Line Items]
Notional amount				$ 23.8
Long [Member] \| Designated as Hedging Instrument [Member] \| United States of America, Dollars \| Foreign Exchange Forward [Member]
Derivative [Line Items]
Notional amount						35.1
Long [Member] \| Designated as Hedging Instrument [Member] \| Japan, Yen \| Foreign Exchange Forward [Member]
Derivative [Line Items]
Notional amount \| ¥					¥ 5,992.8
Short [Member] \| Designated as Hedging Instrument [Member] \| Singapore, Dollars \| Foreign Exchange Forward [Member]
Derivative [Line Items]
Notional amount	€ 1.9					15.4
Short [Member] \| Designated as Hedging Instrument [Member] \| United States of America, Dollars \| Foreign Exchange Forward [Member]
Derivative [Line Items]
Notional amount	30.2					0.0
Short [Member] \| Designated as Hedging Instrument [Member] \| Japan, Yen \| Foreign Exchange Forward [Member]
Derivative [Line Items]
Notional amount	€ 19.8					$ 32.3