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Inventories and natural gas in storage (Tables) | 3 Months Ended
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Mar. 31, 2012
Inventories and natural gas in storage [Abstract] |
Inventories | Inventories consisted of:
| March 31, 2012 |  | March 31, 2011 |  | December 31, 2011 |
| (In thousands)
Aggregates held for resale | $ | 85,958 |  | $ | 82,086 |  | $ | 78,518 |
Asphalt oil | 82,949 |  | 51,506 |  | 32,335 |
Materials and supplies | 68,369 |  | 61,788 |  | 61,611 |
Merchandise for resale | 28,459 |  | 31,830 |  | 32,165 |
Natural gas in storage (current) | 15,475 |  | 11,953 |  | 36,578 |
Other | 32,131 |  | 23,533 |  | 32,998 |
Total | $ | 313,341 |  | $ | 262,696 |  | $ | 274,205 |

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- Definition Tabular disclosure of the carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Topic -SubTopic -Publisher SEC -Number 210 -Article 5 -Subparagraph a,b,c -Name Regulation S-X (SX) -Paragraph 6 -Section 2 + Details
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