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Derivative Instruments (Details) | 12 Months Ended
--- | ---
Jul. 31, 2015 USD ($) | Jul. 31, 2015 NOK
September 2015 [Member] |  |
Derivative [Line Items] |  |
Settlement Date | Sep. 30, 2015 | Sep. 30, 2015
Amount | $ 750,000 | NOK 6,163,000
November 2015 [Member] |  |
Derivative [Line Items] |  |
Settlement Date | Nov. 30, 2015 | Nov. 30, 2015
Amount | $ 2,729,000 | NOK 22,169,000
January 2016 [Member] |  |
Derivative [Line Items] |  |
Settlement Date | Jan. 31, 2016 | Jan. 31, 2016
Amount | $ 3,000,000 | NOK 24,257,000
May 2016 [Member] |  |
Derivative [Line Items] |  |
Settlement Date | May 31, 2016 | May 31, 2016
Amount | $ 1,000,000 | NOK 8,239,000
July 2016 [Member] |  |
Derivative [Line Items] |  |
Settlement Date | Jul. 31, 2016 | Jul. 31, 2016
Amount | $ 1,000,000 | NOK 8,200,000

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- Definition Amount of underlying refers to the price on the security, commodity, index, or other variable specified by the contract. + 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 Date the foreign currency exchange rate derivatives mature or expire, in CCYY-MM-DD format. + References No definition available. + Details
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- Details
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- Details
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