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Comprehensive income (loss) (Tables) | 3 Months Ended
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Mar. 31, 2014
Comprehensive income (loss) [Abstract] |
Comprehensive income (loss) | The after-tax changes in the components of accumulated other comprehensive loss at March 31, 2014, were as follows:
| Net Unrealized Gain (Loss) on Derivative Instruments Qualifying as Hedges | Postretirement Liability Adjustment | Foreign Currency Translation Adjustment | Net Unrealized Gain (Loss) on Available-for-sale Investments | Total Accumulated Other Comprehensive Loss
| (In thousands)
Balance at December 31, 2013 | $ | (3,765 | ) | $ | (33,807 | ) | $ | (667 | ) | $ | 34 |  | $ | (38,205 | )
Other comprehensive income (loss) before reclassifications | — |  | — |  | 46 |  | (36 | ) | 10 |
Amounts reclassified from accumulated other comprehensive loss | 344 |  | 275 |  | — |  | 38 |  | 657 |
Net current-period other comprehensive income | 344 |  | 275 |  | 46 |  | 2 |  | 667 |
Balance at March 31, 2014 | $ | (3,421 | ) | $ | (33,532 | ) | $ | (621 | ) | $ | 36 |  | $ | (37,538 | )
The after-tax changes in the components of accumulated other comprehensive loss at March 31, 2013, were as follows:
| Net Unrealized Gain (Loss) on Derivative Instruments Qualifying as Hedges | Postretirement Liability Adjustment | Foreign Currency Translation Adjustment | Net Unrealized Gain (Loss) on Available-for-sale Investments | Total Accumulated Other Comprehensive Loss
| (In thousands)
Balance at December 31, 2012 | $ | 6,018 |  | $ | (54,347 | ) | $ | (511 | ) | $ | 119 |  | $ | (48,721 | )
Other comprehensive income (loss) before reclassifications | (5,849 | ) | — |  | 88 |  | (44 | ) | (5,805 | )
Amounts reclassified from accumulated other comprehensive loss | (2,772 | ) | 648 |  | — |  | 35 |  | (2,089 | )
Net current-period other comprehensive income (loss) | (8,621 | ) | 648 |  | 88 |  | (9 | ) | (7,894 | )
Balance at March 31, 2013 | $ | (2,603 | ) | $ | (53,699 | ) | $ | (423 | ) | $ | 110 |  | $ | (56,615 | )
Reclassification out of accumulated other comprehensive income | Reclassifications out of accumulated other comprehensive loss were as follows:
| Three Months Ended | Location on Consolidated Statements of Income
| March 31, 2014 | March 31, 2013
| (In thousands) |
Reclassification adjustment for gain (loss) on derivative instruments included in net income: |  |  |
Commodity derivative instruments | $ | (388 | ) | $ | 4,513 |  | Operating revenues
Interest rate derivative instruments | (160 | ) | (115 | ) | Interest expense
| (548 | ) | 4,398 |  |
| 204 |  | (1,626 | ) | Income taxes
| (344 | ) | 2,772 |  |
Amortization of postretirement liability losses included in net periodic benefit cost | (443 | ) | (967 | ) | (a)
| 168 |  | 319 |  | Income taxes
| (275 | ) | (648 | ) |
Reclassification adjustment for loss on available-for-sale investments included in net income | (58 | ) | (54 | ) | Other income
| 20 |  | 19 |  | Income taxes
| (38 | ) | (35 | ) |
Total reclassifications | $ | (657 | ) | $ | 2,089 |  |
(a) Included in net periodic benefit cost (credit). For more information, see Note 17.

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- Definition Tabular disclosure of information about items reclassified out of accumulated other comprehensive income (loss). + References No definition available. + Details
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- Definition Tabular disclosure of the components of accumulated other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669686-108580 + Details
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