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Comprehensive income (loss) (Tables) | 9 Months Ended
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Sep. 30, 2014
Comprehensive income (loss) [Abstract] |
Comprehensive income (loss) | The after-tax changes in the components of accumulated other comprehensive loss were as follows:
Three Months Ended September 30, 2014 | 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 beginning of period | $ | (3,408 | ) | $ | (33,287 | ) | $ | (579 | ) | $ | 76 |  | $ | (37,198 | )
Other comprehensive income (loss) before reclassifications | — |  | — |  | (146 | ) | (62 | ) | (208 | )
Amounts reclassified from accumulated other comprehensive loss | 82 |  | 261 |  | — |  | 31 |  | 374 |
Net current-period other comprehensive income (loss) | 82 |  | 261 |  | (146 | ) | (31 | ) | 166 |
Balance at end of period | $ | (3,326 | ) | $ | (33,026 | ) | $ | (725 | ) | $ | 45 |  | $ | (37,032 | )
Three Months Ended September 30, 2013 | 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 beginning of period | $ | (2,744 | ) | $ | (53,275 | ) | $ | (813 | ) | $ | 11 |  | $ | (56,821 | )
Other comprehensive income (loss) before reclassifications | — |  | — |  | (20 | ) | (10 | ) | (30 | )
Amounts reclassified from accumulated other comprehensive loss | (510 | ) | 272 |  | 114 |  | 38 |  | (86 | )
Net current-period other comprehensive income (loss) | (510 | ) | 272 |  | 94 |  | 28 |  | (116 | )
Balance at end of period | $ | (3,254 | ) | $ | (53,003 | ) | $ | (719 | ) | $ | 39 |  | $ | (56,937 | )
Nine Months Ended September 30, 2014 | 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 beginning of period | $ | (3,765 | ) | $ | (33,807 | ) | $ | (667 | ) | $ | 34 |  | $ | (38,205 | )
Other comprehensive income (loss) before reclassifications | — |  | — |  | (58 | ) | (89 | ) | (147 | )
Amounts reclassified from accumulated other comprehensive loss | 439 |  | 781 |  | — |  | 100 |  | 1,320 |
Net current-period other comprehensive income (loss) | 439 |  | 781 |  | (58 | ) | 11 |  | 1,173 |
Balance at end of period | $ | (3,326 | ) | $ | (33,026 | ) | $ | (725 | ) | $ | 45 |  | $ | (37,032 | )
Nine Months Ended September 30, 2013 | 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 beginning of period | $ | 6,018 |  | $ | (54,347 | ) | $ | (511 | ) | $ | 119 |  | $ | (48,721 | )
Other comprehensive income (loss) before reclassifications | (5,594 | ) | — |  | (351 | ) | (197 | ) | (6,142 | )
Amounts reclassified from accumulated other comprehensive loss | (3,678 | ) | 1,344 |  | 143 |  | 117 |  | (2,074 | )
Net current-period other comprehensive income (loss) | (9,272 | ) | 1,344 |  | (208 | ) | (80 | ) | (8,216 | )
Balance at end of period | $ | (3,254 | ) | $ | (53,003 | ) | $ | (719 | ) | $ | 39 |  | $ | (56,937 | )
Reclassification out of accumulated other comprehensive income | Reclassifications out of accumulated other comprehensive loss were as follows:
| Three Months Ended | Nine Months Ended | Location on Consolidated Statements of Income
| September 30, | September 30,
| 2014 | 2013 | 2014 | 2013
| (In thousands) |
Reclassification adjustment for gain (loss) on derivative instruments included in net income: |  |  |  |  |
Commodity derivative instruments | $ | 28 |  | $ | 1,007 |  | $ | (223 | ) | $ | 6,903 |  | Operating revenues
Interest rate derivative instruments | (160 | ) | (200 | ) | (480 | ) | (979 | ) | Interest expense
| (132 | ) | 807 |  | (703 | ) | 5,924 |  |
| 50 |  | (297 | ) | 264 |  | (2,246 | ) | Income taxes
| (82 | ) | 510 |  | (439 | ) | 3,678 |  |
Amortization of postretirement liability losses included in net periodic benefit cost | (420 | ) | (437 | ) | (1,258 | ) | (2,371 | ) | (a)
| 159 |  | 166 |  | 477 |  | 1,027 |  | Income taxes
| (261 | ) | (271 | ) | (781 | ) | (1,344 | ) |
Reclassification adjustment for loss on foreign currency translation adjustment included in net income | — |  | (185 | ) | — |  | (213 | ) | Earnings (loss) from equity method investments
| — |  | 70 |  | — |  | 70 |  | Earnings (loss) from equity method investments
| — |  | (115 | ) | — |  | (143 | ) |
Reclassification adjustment for loss on available-for-sale investments included in net income | (47 | ) | (58 | ) | (154 | ) | (180 | ) | Other income
| 16 |  | 20 |  | 54 |  | 63 |  | Income taxes
| (31 | ) | (38 | ) | (100 | ) | (117 | ) |
Total reclassifications | $ | (374 | ) | $ | 86 |  | $ | (1,320 | ) | $ | 2,074 |  |
(a) Included in net periodic benefit cost (credit). For more information, see Note 20.

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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=36458714&loc=SL7669686-108580 + Details
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