Significant Accounting Policies	6 Months Ended
Jun. 30, 2018
Significant Accounting Policies [Abstract]
Significant Accounting Policies	2. Significant Accounting Policies Revenue Recognition The FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606). ASU No. 2014-09, as subsequently amended, supersedes the revenue recognition requirements in Revenue Recognition (Topic 605), and most industry-specific guidance throughout the Industry Topics of the Codification. Additionally, ASU No. 2014-09 supersedes some cost guidance included in Revenue Recognition-Construction-Type and Production-Type Contracts (Subtopic 605-35). Under ASU No. 2014-09, an entity should recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU No. 2014-09 also requires additional disclosure about the nature, amount, timing, and uncertainty of revenue and cash flows arising from customer contracts. This includes significant judgments and changes in judgments and assets recognized from costs incurred to obtain or fulfill a contract. The new guidance is effective for interim and annual periods beginning after December 15, 2017. Effective January 1, 2018, the Company adopted the new guidance retrospectively. The Company performed an assessment of the revised guidance and the impacts on the Company’s Consolidated Financial Statements and disclosures. We also evaluated the potential for future variable consideration from option payments, net smelter return royalties (“NSR”), and other production related payments, and determined that there is no impact to the Company’s current accounting. The Company determined that the adoption of this guidance will primarily impact the timing of revenue recognition on certain option agreements based on the Company’s determination of when control is transferred for accounting purposes. Based on the contracts outstanding as of December 31, 2017, there was no cumulative effect adjustment required to be recognized at January 1, 2018. Under the Company’s adoption approach, results for reporting periods beginning after January 1, 2018, will be presented in the Consolidated Financial Statements under the new guidance, while prior period amounts will not be adjusted and continue to be reported under the guidance in effect for those periods. Currently, proceeds received from option agreements are ascribed to recovery of the carrying value of the related project until the carrying value reaches zero. After that, any additional proceeds received will be recognized as a contract liability until control has transferred to the buyer or the related contract has terminated. None of the projects which could provide the Company with future variable consideration are currently in production, and in all cases, we believe there is low probability of future production from these projects. Accordingly, the Company believes its NSRs and other production related payments are fully constrained, and the Company did not record a receivable for them. When it becomes probable that a project which could provide the Company with an NSR or other production related payments could begin production, the Company will evaluate the accounting treatment at that time.

2. Significant Accounting Policies

Revenue Recognition

The FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606). ASU No. 2014-09, as subsequently amended, supersedes the revenue recognition requirements in Revenue Recognition (Topic 605), and most industry-specific guidance throughout the Industry Topics of the Codification. Additionally, ASU No. 2014-09 supersedes some cost guidance included in Revenue Recognition-Construction-Type and Production-Type Contracts (Subtopic 605-35). Under ASU No. 2014-09, an entity should recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU No. 2014-09 also requires additional disclosure about the nature, amount, timing, and uncertainty of revenue and cash flows arising from customer contracts. This includes significant judgments and changes in judgments and assets recognized from costs incurred to obtain or fulfill a contract. The new guidance is effective for interim and annual periods beginning after December 15, 2017.

Effective January 1, 2018, the Company adopted the new guidance retrospectively. The Company performed an assessment of the revised guidance and the impacts on the Company’s Consolidated Financial Statements and disclosures. We also evaluated the potential for future variable consideration from option payments, net smelter return royalties (“NSR”), and other production related payments, and determined that there is no impact to the Company’s current accounting. The Company determined that the adoption of this guidance will primarily impact the timing of revenue recognition on certain option agreements based on the Company’s determination of when control is transferred for accounting purposes. Based on the contracts outstanding as of December 31, 2017, there was no cumulative effect adjustment required to be recognized at January 1, 2018. Under the Company’s adoption approach, results for reporting periods beginning after January 1, 2018, will be presented in the Consolidated Financial Statements under the new guidance, while prior period amounts will not be adjusted and continue to be reported under the guidance in effect for those periods.

Currently, proceeds received from option agreements are ascribed to recovery of the carrying value of the related project until the carrying value reaches zero. After that, any additional proceeds received will be recognized as a contract liability until control has transferred to the buyer or the related contract has terminated. None of the projects which could provide the Company with future variable consideration are currently in production, and in all cases, we believe there is low probability of future production from these projects. Accordingly, the Company believes its NSRs and other production related payments are fully constrained, and the Company did not record a receivable for them. When it becomes probable that a project which could provide the Company with an NSR or other production related payments could begin production, the Company will evaluate the accounting treatment at that time.