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Inventories and natural gas in storage (Tables) | 9 Months Ended
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Sep. 30, 2012
Inventories and natural gas in storage [Abstract] |
Inventories | Inventories consisted of:
| September 30, 2012 | September 30, 2011 | December 31, 2011
| (In thousands)
Aggregates held for resale | $ | 88,632 |  | $ | 80,868 |  | $ | 78,518 |
Materials and supplies | 75,551 |  | 64,988 |  | 61,611 |
Asphalt oil | 47,084 |  | 26,851 |  | 32,335 |
Natural gas in storage (current) | 41,091 |  | 39,629 |  | 36,578 |
Merchandise for resale | 30,827 |  | 30,974 |  | 32,165 |
Other | 32,582 |  | 26,259 |  | 32,998 |
Total | $ | 315,767 |  | $ | 269,569 |  | $ | 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 -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 2 -Paragraph 6 -Subparagraph a,b,c -Article 5 + Details
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