Royalty Interests (Details) $ in Thousands |
9 Months Ended | 12 Months Ended | |
|---|---|---|---|
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Sep. 30, 2019
USD ($)
a
$ / a
|
Sep. 30, 2018
USD ($)
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Dec. 31, 2018
USD ($)
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|
| Net Book Value | |||
| Royalty interests acquired | $ 29,320 | $ 24,303 | |
| Total royalty interests | 29,320 | $ 24,303 | |
| Acquisition of royalty interests | $ 5,017 | $ 0 | |
| 1/16th Nonparticipating Perpetual Royalty Interest | |||
| Real Estate Properties [Line Items] | |||
| Nonparticipating perpetual royalty interest rate | 6.25% | 6.25% | |
| Net Book Value | |||
| 1/16th nonparticipating perpetual royalty interest | $ 0 | $ 0 | |
| 1/128th Nonparticipating Perpetual Royalty Interest | |||
| Real Estate Properties [Line Items] | |||
| Nonparticipating perpetual royalty interest rate | 0.78125% | 0.78125% | |
| Net Book Value | |||
| 1/128th nonparticipating perpetual royalty interest | $ 0 | $ 0 | |
| Additional real estate acquisitions | |||
| Net Book Value | |||
| Net royalty interests (acre) | a | 1,247 | ||
| Acquisition of royalty interests | $ 4,700 | ||
| Average price per net royalty acre acquired (in dollars per acre) | $ / a | 3,800 | ||
| X | ||||||||||
- Definition Average Price Per Net Royalty Acre Acquired No definition available.
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- Definition Net Book Value of Royalty Interests [Abstract] No definition available.
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- Definition An expense-free interest with a perpetual duration in oil or gas, as, if and when produced 1/128 of the proceeds are due to the Trust. Nonparticipating indicates the interest does not share in bonus or rental, nor in the right to execute leases or to explore and develop. No definition available.
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- Definition An expense-free interest with a perpetual duration in oil or gas, as, if and when produced 1/16 of the proceeds are due to the Trust. Nonparticipating indicates the interest does not share in bonus or rental, nor in the right to execute leases or to explore and develop. No definition available.
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- Definition Nonparticipating Perpetual Royalty Interest Rate No definition available.
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- Definition Royalty Interest Acquired No definition available.
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- Definition Royalty Interest Acquired, Acres No definition available.
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- Definition Total Royalty Interests No definition available.
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- Definition The cash outflow from the purchase of royalty interests in mining properties is the amount of cash the mineral producer pays the owner of the mine or mineral resource. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition 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. No definition available.
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