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Regulatory assets and liabilities (Tables) | 12 Months Ended
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Dec. 31, 2012
Regulatory Assets and Liabilities Disclosure [Abstract] |
Regulatory assets and liabilities | The following table summarizes the individual components of unamortized regulatory assets and liabilities as of December 31:
| Estimated Recovery Period |  | * | 2012 |  | 2011 |
|  |  | (In thousands)
Regulatory assets: |  |  |  |
Pension and postretirement benefits (a) | (e) |  |  | $ | 166,477 |  | $ | 171,492 |
Deferred income taxes | ** |  |  | 121,781 |  | 119,189 |
Manufactured gas plant sites remediation (a) | Up to 5 years |  |  | 15,828 |  | 8,150 |
Plant costs (a) | Over plant lives |  |  | 10,348 |  | 10,256 |
Long-term debt refinancing costs (a) | Up to 25 years |  |  | 9,144 |  | 10,112 |
Taxes recoverable from customers (a) | — |  |  | 9,078 |  | 12,433 |
Costs related to identifying generation development (a) | Up to 14 years |  |  | 5,773 |  | 9,817 |
Other (a) (b) | Largely within 1 year |  |  | 12,765 |  | 17,560 |
Total regulatory assets |  |  |  | 351,194 |  | 359,009 |
Regulatory liabilities: |  |  |  |  |
Plant removal and decommissioning costs (c) |  |  |  | 296,037 |  | 289,972 |
Deferred income taxes** |  |  |  | 82,077 |  | 84,963 |
Natural gas costs refundable through rate adjustments (d) |  |  |  | 35,328 |  | 45,064 |
Taxes refundable to customers (c) |  |  |  | 24,212 |  | 31,837 |
Other (c) (d) |  |  |  | 12,828 |  | 8,393 |
Total regulatory liabilities |  |  |  | 450,482 |  | 460,229 |
Net regulatory position |  |  |  | $ | (99,288 | ) | $ | (101,220 | )
* Estimated recovery period for regulatory assets currently being recovered in rates charged to customers. ** Represents deferred income taxes related to regulatory assets and liabilities. The deferred income tax assets are not earning a rate of return. (a) Included in deferred charges and other assets on the Consolidated Balance Sheets. (b) Included in prepayments and other current assets on the Consolidated Balance Sheets. (c) Included in other liabilities on the Consolidated Balance Sheets. (d) Included in other accrued liabilities on the Consolidated Balance Sheets. (e) Recovered as expense is incurred.

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- Definition Tabular disclosure of detailed information about regulatory assets and liabilities, including current and noncurrent assets created when regulatory agencies permit the deferral of costs to the balance sheet that would otherwise be required to appear on the company's income statement and would be charged against current expenses or revenues, as well as current and noncurrent liabilities created when regulatory agencies permit. + References No definition available. + Details
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- Details
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