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v3.19.1

Deferred Consideration - Additional Information (Detail) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 USD ($) oz | Dec. 31, 2018 USD ($)
Business Acquisition [Line Items] |  |
Fixed payment ounces of gold | oz | 2,375 |
Upfront consideration paid | $ 0 |
Deferred consideration | 157,147,000 | $ 161,540,000
Deferred consideration, current | 11,857,000 | 11,765,000
Deferred consideration, non-current | $ 145,290,000 | $ 149,775,000
Discount rate used to value the deferred consideration | 10.00% |
Contractual gold payments | $ 3,098,000 |
Gain/loss on revaluation of deferred consideration | $ 4,404,000 |
April 1, 2018 through March 31, 2058 [Member] |  |
Business Acquisition [Line Items] |  |
Fixed payment ounces of gold | oz | 9,500 |
April 1, 2058 and Thereafter [Member] |  |
Business Acquisition [Line Items] |  |
Fixed payment ounces of gold | oz | 6,333 |

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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. + References No definition available. + Details
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- Definition Discount rate used to value the deferred consideration. + References No definition available. + Details
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- Definition Amount of liability arising from deferred consideration in a business combination. + References No definition available. + Details
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- Definition Contractual gold payments. + References No definition available. + Details
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- Definition Deferred consideration - noncurrent. + References No definition available. + Details
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- Definition Gain/loss from revaluation of deferred consideration. + References No definition available. + Details
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- Details
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- Details
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