Accounting Policies - Inventory (Details 5) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Inventory and natural gas in storage [Line Items]
Aggregates held for resale	$ 175,782	$ 147,723
Asphalt oil	28,238	41,912
Materials and supplies	25,142	22,512
Merchandise for resale	21,087	22,232
Natural gas in storage (current)	21,919	22,058
Other	18,999	21,970
Total	291,167	278,407
Natural gas in storage (noncurrent)	$ 47,500	$ 48,400

Aggregated amount of aggregates held for resale. This amount is net of valuation reserves and adjustments.

No definition available.

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- Definition

Aggregated amount of asphalt oil inventory. This amount is net of valuation reserves and adjustments.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of natural gas in storage, which is a mixture of gases (liquefied or otherwise), used for fuel and manufacturing purposes, which is ready for sale.

+ References

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- Definition

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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- Definition

Carrying amount as of the balance sheet date of natural gas stored underground in depleted gas reservoirs, aquifers, or salt caverns to meet future seasonal and peak load demands and also as insurance against unforeseen supply disruptions, and deemed to be a noncurrent asset because it is not expected to be used within 12 months or in the normal operating cycle.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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- Definition

Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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- Definition

Amount, after of valuation reserves and allowances, of inventory, classified as other, expected to be sold, or consumed within one year or operating cycle, if longer.

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