Unconsolidated Subsidiaries (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Variable Interest Entity [Line Items]
Investments in unconsolidated subsidiaries and related tax positions	$ 20,927		$ 20,927		$ 28,978
Variable interest entity, reporting entity involvement, maximum risk of loss	5,500		5,500		6,500
Earnings of unconsolidated operations	13,542	$ 13,778	28,884	$ 29,781
Other noncurrent assets
Variable Interest Entity [Line Items]
Investments in unconsolidated subsidiaries and related tax positions	$ 20,900		$ 20,900		$ 29,000

This item represents the entity's proportionate share for the period of the pre-tax earnings of the unconsolidated mines to which the equity method of accounting is applied. Income tax amounts are included in the income tax provision line.

No definition available.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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