XML 56 R45.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Financial Instruments and Risk Management (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2018
Financial Instruments and Risk Management [Abstract] |
Fair Value of Derivative Instruments Not Designated as Hedging Instruments |
﻿ |  |  |  |  |  |  |  |
﻿ |  |  |  |  |  |  |  |
﻿ |  | December 31, 2018 |  | December 31, 2017
﻿(Thousands of dollars) |  | Asset (Liability) Derivatives |  | Asset (Liability) Derivatives
﻿Type of Derivative Contract |  | Balance Sheet Location |  | Fair Value |  | Balance Sheet Location |  | Fair Value
﻿Commodity |  | Accounts receivable | $ | 3,837 |  | Accounts payable | $ | (39,093)
﻿
Recognized Gains and Losses for Derivative Instruments Not Designated as Hedging Instruments |
﻿ |  |  |  |  |  |  |  |  |
﻿ |  |  |  |  |  |  |  |  |
﻿ |  |  |  | Gain (Loss)
﻿(Thousands of dollars) |  |  |  |  | Year Ended December 31,
﻿Type of Derivative Contract |  | Statement of Operations Locations |  | 2018 |  | 2017 |  | 2016
﻿Commodity |  | (Loss) gain on crude contracts |  | $ | (41,975) |  | 9,566 |  | (63,412)
﻿Foreign exchange |  | Interest and other income (loss) |  |  | – |  | – |  | 26,714
﻿ |  |  |  | $ | (41,975) |  | 9,566 |  | (36,698)
﻿

X
- References No definition available. + Details
Name: | us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the location and amount of derivative instruments and nonderivative instruments designated as hedging instruments reported before netting adjustments, and the amount of gain (loss) on derivative instruments and nonderivative instruments designated and qualified as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959 + Details
Name: | us-gaap_ScheduleOfDerivativeInstrumentsGainLossInStatementOfFinancialPerformanceTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the location and fair value amounts of derivative instruments (and nonderivative instruments that are designated and qualify as hedging instruments) reported in the statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959 + Details
Name: | us-gaap_ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration