Asset Retirement Obligation (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||||
|---|---|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
Dec. 31, 2018 |
Mar. 31, 2017 |
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| Asset retirement obligation | $ 767 | $ 767 | $ 745 | $ 700 | ||
| Accretion expense | 11,000 | $ 11,000 | 23,000 | $ 21,000 | ||
| Other Assets | ||||||
| Contributed to the Trust Fund | $ 670,000 | $ 670,000 | ||||
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- Definition Refers to contribution of fund. No definition available.
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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 Noncurrent portion of 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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- Details
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