Asset Retirement Obligations (Details) - USD ($) |
3 Months Ended | |
|---|---|---|
Mar. 31, 2021 |
Mar. 31, 2020 |
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| Asset Retirement Obligations | ||
| Beginning of period | $ 29,965,000 | |
| Change in estimated reclamation costs | 0 | |
| Accretion expense | 123,000 | $ 145,000 |
| End of period | $ 30,088,000 | |
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- Definition Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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