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Financial Instruments and Risk Management (Interest Rate Risk) (Details) - Interest rate risk [member] $ in Millions | 12 Months Ended
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Dec. 31, 2017 USD ($)
Disclosure of nature and extent of risks arising from financial instruments [line items] |
Potential percentage change in value | 100.00%
Impact on interest earned | $ 2.0

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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Details
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