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Inventories and natural gas in storage | 6 Months Ended
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Jun. 30, 2013
Inventories and natural gas in storage [Abstract] |
Inventories and natural gas in storage | 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:
| June 30, 2013 | June 30, 2012 | December 31, 2012
| (In thousands)
Aggregates held for resale | $ | 103,503 |  | $ | 90,992 |  | $ | 87,715 |
Asphalt oil | 91,837 |  | 81,915 |  | 67,480 |
Materials and supplies | 74,648 |  | 72,321 |  | 69,390 |
Merchandise for resale | 27,330 |  | 30,417 |  | 31,172 |
Natural gas in storage (current) | 14,287 |  | 26,216 |  | 29,030 |
Other | 34,280 |  | 31,531 |  | 32,628 |
Total | $ | 345,885 |  | $ | 333,392 |  | $ | 317,415 |
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 $48.6 million, $50.3 million, and $49.7 million at June 30, 2013 and 2012, and December 31, 2012, respectively.

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- Definition The entire disclosure for inventory. This may include, but is not limited to, the basis of stating inventory, the method of determining inventory cost, the major classes of inventory, and the nature of the cost elements included in inventory. If inventory is stated above cost, accrued net losses on firm purchase commitments for inventory and losses resulting from valuing inventory at the lower-of-cost-or-market may also be included. For LIFO inventory, may disclose the amount and basis for determining the excess of replacement or current cost over stated LIFO value and the effects of a LIFO quantities liquidation that impacts net income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 6 -Subparagraph a, b, c -Article 5 + Details
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