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Inventories and natural gas in storage | 9 Months Ended
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Sep. 30, 2011
Inventories and natural gas in storage [Abstract] |
Inventories and natural gas in storage |
4. | Inventories and natural gas in storage
| Inventories, other than natural gas in storage for the Company's regulated operations, were stated at the lower of average cost or market value. Natural gas in storage for the Company's regulated operations is generally carried at average cost, or cost using the last-in, first-out method. The portion of the cost of natural gas in storage expected to be used within one year was included in inventories. Inventories consisted of:
|  | September 30, 2011 |  |  | September 30, 2010 |  |  | December 31, 2010 |
|  | (In thousands) |
Aggregates held for resale |  | $ | 80,868 |  |  | $ | 82,622 |  |  | $ | 79,894 |
Materials and supplies |  |  | 64,988 |  |  |  | 62,273 |  |  |  | 57,324 |
Natural gas in storage (current) |  |  | 39,629 |  |  |  | 40,133 |  |  |  | 34,557 |
Merchandise for resale |  |  | 30,974 |  |  |  | 29,566 |  |  |  | 30,182 |
Asphalt oil |  |  | 26,851 |  |  |  | 24,341 |  |  |  | 25,234 |
Other |  |  | 26,259 |  |  |  | 22,745 |  |  |  | 25,706 |
Total |  | $ | 269,569 |  |  | $ | 261,680 |  |  | $ | 252,897 |
| The remainder of natural gas in storage, which largely represents the cost of gas required to maintain pressure levels for normal operating purposes, was included in other assets and was $47.2 million, $59.3 million, and $48.0 million at September 30, 2011 and 2010, and December 31, 2010, respectively.

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