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Derivative instruments (Tables) | 3 Months Ended
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Mar. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract] |
Schedule of derivative instruments, gain (losses) | The gains and losses on derivative instruments were as follows:
| Three Months Ended
| March 31,
| 2016 | 2015
| (In thousands)
Interest rate derivatives designated as cash flow hedges: |  |
Amount of loss reclassified from accumulated other comprehensive loss into interest expense (effective portion), net of tax | 92 |  | 99 |
Commodity derivatives not designated as hedging instruments: |  |
Amount of gain (loss) recognized in discontinued operations, before tax | — |  | (11,208 | )
Derivative instruments | The location and fair value of the gross amount of the Company's derivative instruments on the Consolidated Balance Sheets were as follows:
Asset Derivatives | Location on Consolidated Balance Sheets | Fair Value at March 31, 2015 |
|  | (In thousands)
Not designated as hedges: |
Commodity derivatives | Current assets held for sale | $ | 7,127 |
Total asset derivatives |  | $ | 7,127 |
Offsetting assets and liabilities master netting | The gross derivative assets and liabilities (excluding settlement receivables and payables that may be subject to the same master netting agreements) presented on the Consolidated Balance Sheets and the amount eligible for offset under the master netting agreements is presented in the following table:
March 31, 2015 | Gross Amounts Recognized on the Consolidated Balance Sheets |  | Gross Amounts Not Offset on the Consolidated Balance Sheets |  | Net |
| (In thousands)
Assets: |  |  |
Commodity derivatives | $ | 7,127 |  | $ | — |  | $ | 7,127 |
Total assets | $ | 7,127 |  | $ | — |  | $ | 7,127 |

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- 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=64837297&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=64837297&loc=SL5618551-113959 + Details
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- 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=64837297&loc=SL5624163-113959 + Details
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