Derivative Instruments and Hedging Activities (Schedule of Derivative Instruments in Statement of Financial Position, Fair Value) (Details) - Not Designated as Hedging Instrument - USD ($) $ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Offsetting Assets and Liabilities [Line Items] | ||
| Derivative Assets | $ 406 | $ 103 |
| Derivative Liabilities | (29,028) | (18,296) |
| Current Assets | ||
| Offsetting Assets and Liabilities [Line Items] | ||
| Derivative asset, fair value, gross asset | 406 | 1,836 |
| Derivative asset, fair value, gross liability | 0 | (1,733) |
| Derivative Assets | 406 | 103 |
| Current Liabilities | ||
| Offsetting Assets and Liabilities [Line Items] | ||
| Derivative liability, fair value, gross liability | (27,744) | (20,001) |
| Derivative liability, fair value, gross asset | 0 | 1,733 |
| Derivative Liabilities | (27,744) | (18,268) |
| Non-current Liabilities | ||
| Offsetting Assets and Liabilities [Line Items] | ||
| Derivative liability, fair value, gross liability | (1,284) | (28) |
| Derivative liability, fair value, gross asset | 0 | 0 |
| Derivative Liabilities | $ (1,284) | $ (28) |
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- Definition [Line Items] for Offsetting Assets and Liabilities [Table] No definition available.
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- Definition Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value of asset associated with financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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