Change in Accounting Principle	12 Months Ended
Dec. 31, 2019
Change in Accounting Principle
Change in Accounting Principle	5. Change in Accounting Principle Leases Effective January 1, 2019 the Company adopted ASU 2016-02 and ASU 2018-11, which requires lessees to recognize a right-of-use asset and a lease liability for all leases with terms greater than twelve months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. For a lessor, the accounting applied is largely unchanged from previous guidance. The Company currently leases administrative offices in the U.S. and in several foreign locations under lease agreements that typically exceed one year. The Company has elected the modified retrospective method of adopting ASU 2016-02 per Topic 842. The Company has elected to apply several practical expedients available under the application of ASU 2016-02 and ASU 2018-11, which allowed the Company to forego reassessing the classification of existing or expiring leases, evaluating whether any existing or expiring contracts contain leases or reassessing previously recorded indirect costs. The Company did not elect the practical expedient permitting the combination of lease and non lease components of the contract. The adoption of ASU 2016-02 and ASU 2018-11 at January 1, 2019 resulted in only a negligible difference to amounts already recorded by the Company in its Consolidated Balance Sheets as of December 31, 2018, and as result the Company did not record an adjustment to the beginning balance of retained earnings at January 1, 2019, as required under the modified retrospective method. The Company took possession of new office space and began a new long-term lease for its principal headquarters office with an effective commencement date of June 1, 2019. The new office lease will expire five years and eight full calendar months following the commencement date. There are no options to extend the lease beyond the stated term. The Company recorded a right of use asset of approximately $465,000 and a lease liability of approximately $450,000 in the second quarter of 2019 based on the net present value of the future lease payments discounted at 9.5%, which represents the Company’s incremental borrowing rate for purposes of applying the guidance of Topic 842. As required, the Company will recognize a single lease cost on a straight-line basis. The Company also has long-term office leases in Mexico and Argentina that expired in 2019 and recorded a combined lease liability of approximately $45,000 and combined right of use asset of approximately $45,000 relating to both of those leases at January 1, 2019. In November 2019, the Company renewed its Mexican office lease for four years and recorded a right of use asset and lease liability of approximately $174,000. In December 2019, the Company also renewed its Argentina office lease for two years and recorded a right of use asset and lease liability of approximately $18,000. The Company has included its right of use assets for the office leases described above in “Other long-term assets” (Note 11) and its office lease liabilities in “Other liabilities”, short term and long term (Note 14), in the Company’s Consolidated Balance Sheets for the period ended December 31, 2019. Other Income Related to the Sale of Exploration Properties During the first quarter 2018 the Company adopted ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606)” (“ASU 2014-09”) which was issued by the FASB in May 2014. ASU 2014-09 outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. In addition, the guidance requires improved disclosures to help users of financial statements better understand the nature, amount, timing and uncertainty of revenue that is recognized and the related cash flows. The Company has elected the modified retrospective method of initially adopting ASU 2014-09. ASU 2014-09 requires, in certain instances, that transactions covered by ASC Topic 610, “Other Income” (“Topic 610”) follow the recognition, measurement and disclosure guidelines established by ASU 2014-09. The Company generally follows the guidance of Topic 610 with respect to the recognition of income from the farm-out or sale of exploration properties. As of the beginning of 2018, the Company had one open contract impacted by the adoption of ASU 2014-09, involving an option agreement under which Santacruz Silver Mining Ltd. (“Santacruz”) may acquire the Company’s interest in certain nonstrategic mineral claims located in the Zacatecas Mining District, Zacatecas, Mexico (the “Zacatecas Properties”) for a series of payments totaling $1.5 million (Note 10). In applying ASU 2014-09, approximately $49,000 of the income recognized from the Santacruz transaction in the fourth quarter of 2017 would have been recognized in the first quarter of 2018. Accordingly, the Company has recognized retrospectively the cumulative effect of initially adopting ASU 2014-09 by recording a negative adjustment to retained earnings of $49,000 at the beginning of 2018, included in the Company’s Consolidated Statement of Changes in Equity, and recording $49,000 in “Other operating income, net” in the accompanying Consolidated Statements of Operations for the period ended December 31, 2018. See Note 10 for a further description of the contract with Santacruz and the identification of performance obligations and other significant judgments used in applying the guidance of Topic 606 to the contract. Available for Sale Securities During the first quarter 2018 the Company adopted ASU No. 2016-01, which amended its accounting treatment for the recognition, measurement, presentation and disclosure of certain financial assets. ASU 2016-01 requires equity investments that have readily determinable fair values to be measured at fair value through net income. Previously, entities would recognize changes in fair value of available-for-sale equity securities in other comprehensive income and would recognize in net income impairment losses that were other-than-temporary. There will no longer be an available-for-sale classification (with changes in fair value reported in other comprehensive income) for equity securities with readily determinable fair values. At December 31, 2017, the Company had equity securities classified as available-for-sale and reported at fair value of $238,000, with cumulative unrealized losses of $40,000 recorded in “Accumulated other comprehensive loss” on its Consolidated Balance Sheets. The Company has recognized the cumulative effect of initially adopting ASU 2016-01 by recording a negative adjustment to retained earnings and other comprehensive income of $40,000 at the beginning of 2018, included in the Company’s Consolidated Statement of Changes in Equity, and has recorded a gain of approximately $51,000 in “Interest and other income, net” in the accompanying Consolidated Statements of Operations for the period ended December 31, 2018. Warrant Liability In July 2017, the FASB issued ASU 2017-11, “Earnings Per Share (Topic 260); Distinguishing Liabilities from Equity (Topic 480); Derivatives and Hedging (Topic 815): (Part 1) Accounting for Certain Financial Instruments with Down Round Features, (Part II) Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception” (“ASU 2017-11”). For freestanding equity-classified financial instruments, ASU 2017-11 requires entities that present earnings per share (EPS) in accordance with Topic 260 to recognize the effect of the down round feature when it is triggered. That effect is treated as a dividend and as a reduction of income available to common shareholders in basic EPS. Certain equity transactions following the issuance of the 2014 warrants have triggered anti-dilution clauses in the warrant agreements resulting in additional warrant shares and a reduction to the original strike price of the warrants. ASU 2017-11 prescribes a method to measure the value of a deemed dividend related to a triggering event by computing the difference in fair value between two instruments that have terms consistent with the actual instrument but that do not have a down round feature, where the number of warrant shares and strike price of one instrument corresponds to the actual instrument before the triggering event and the number of warrant shares and strike price of the other instrument corresponds to the actual instrument immediately after the triggering event. Following ASU 2017-11, for the years ending December 31, 2019 and December 31, 2018, the Company reduced its accumulated deficit by approximately $3,000 and $8,000 respectively related to triggering events.

5. Change in Accounting Principle

Leases

Effective January 1, 2019 the Company adopted ASU 2016-02 and ASU 2018-11, which requires lessees to recognize a right-of-use asset and a lease liability for all leases with terms greater than twelve months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. For a lessor, the accounting applied is largely unchanged from previous guidance. The Company currently leases administrative offices in the U.S. and in several foreign locations under lease agreements that typically exceed one year. The Company has elected the modified retrospective method of adopting ASU 2016-02 per Topic 842. The Company has elected to apply several practical expedients available under the application of ASU 2016-02 and ASU 2018-11, which allowed the Company to forego reassessing the classification of existing or expiring leases, evaluating whether any existing or expiring contracts contain leases or reassessing previously recorded indirect costs. The Company did not elect the practical expedient permitting the combination of lease and non lease components of the contract. The adoption of ASU 2016-02 and ASU 2018-11 at January 1, 2019 resulted in only a negligible difference to amounts already recorded by the Company in its Consolidated Balance Sheets as of December 31, 2018, and as result the Company did not record an adjustment to the beginning balance of retained earnings at January 1, 2019, as required under the modified retrospective method.

The Company took possession of new office space and began a new long-term lease for its principal headquarters office with an effective commencement date of June 1, 2019. The new office lease will expire five years and eight full calendar months following the commencement date. There are no options to extend the lease beyond the stated term. The Company recorded a right of use asset of approximately $465,000 and a lease liability of approximately $450,000 in the second quarter of 2019 based on the net present value of the future lease payments discounted at 9.5%, which represents the Company’s incremental borrowing rate for purposes of applying the guidance of Topic 842. As required, the Company will recognize a single lease cost on a straight-line basis.

The Company also has long-term office leases in Mexico and Argentina that expired in 2019 and recorded a combined lease liability of approximately $45,000 and combined right of use asset of approximately $45,000 relating to both of those leases at January 1, 2019. In November 2019, the Company renewed its Mexican office lease for four years and recorded a right of use asset and lease liability of approximately $174,000. In December 2019, the Company also renewed its Argentina office lease for two years and recorded a right of use asset and lease liability of approximately $18,000.

The Company has included its right of use assets for the office leases described above in “Other long-term assets” (Note 11) and its office lease liabilities in “Other liabilities”, short term and long term (Note 14), in the Company’s Consolidated Balance Sheets for the period ended December 31, 2019.

Other Income Related to the Sale of Exploration Properties

During the first quarter 2018 the Company adopted ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606)” (“ASU 2014-09”) which was issued by the FASB in May 2014. ASU 2014-09 outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. In addition, the guidance requires improved disclosures to help users of financial statements better understand the nature, amount, timing and uncertainty of revenue that is recognized and the related cash flows. The Company has elected the modified retrospective method of initially adopting ASU 2014-09.

ASU 2014-09 requires, in certain instances, that transactions covered by ASC Topic 610, “Other Income” (“Topic 610”) follow the recognition, measurement and disclosure guidelines established by ASU 2014-09. The Company generally follows the guidance of Topic 610 with respect to the recognition of income from the farm-out or sale of exploration properties. As of the beginning of 2018, the Company had one open contract impacted by the adoption of ASU 2014-09, involving an option agreement under which Santacruz Silver Mining Ltd. (“Santacruz”) may acquire the Company’s interest in certain nonstrategic mineral claims located in the Zacatecas Mining District, Zacatecas, Mexico (the “Zacatecas Properties”) for a series of payments totaling $1.5 million (Note 10). In applying ASU 2014-09, approximately $49,000 of the income recognized from the Santacruz transaction in the fourth quarter of 2017 would have been recognized in the first quarter of 2018. Accordingly, the Company has recognized retrospectively the cumulative effect of initially adopting ASU 2014-09 by recording a negative adjustment to retained earnings of $49,000 at the beginning of 2018, included in the Company’s Consolidated Statement of Changes in Equity, and recording $49,000 in “Other operating income, net” in the accompanying Consolidated Statements of Operations for the period ended December 31, 2018. See Note 10 for a further description of the contract with Santacruz and the identification of performance obligations and other significant judgments used in applying the guidance of Topic 606 to the contract.

Available for Sale Securities

During the first quarter 2018 the Company adopted ASU No. 2016-01, which amended its accounting treatment for the recognition, measurement, presentation and disclosure of certain financial assets. ASU 2016-01 requires equity investments that have readily determinable fair values to be measured at fair value through net income. Previously, entities would recognize changes in fair value of available-for-sale equity securities in other comprehensive income and would recognize in net income impairment losses that were other-than-temporary. There will no longer be an available-for-sale classification (with changes in fair value reported in other comprehensive income) for equity securities with readily determinable fair values. At December 31, 2017, the Company had equity securities classified as available-for-sale and reported at fair value of $238,000, with cumulative unrealized losses of $40,000 recorded in “Accumulated other comprehensive loss” on its Consolidated Balance Sheets. The Company has recognized the cumulative effect of initially adopting ASU 2016-01 by recording a negative adjustment to retained earnings and other comprehensive income of $40,000 at the beginning of 2018, included in the Company’s Consolidated Statement of Changes in Equity, and has recorded a gain of approximately $51,000 in “Interest and other income, net” in the accompanying Consolidated Statements of Operations for the period ended December 31, 2018.

Warrant Liability

In July 2017, the FASB issued ASU 2017-11, “Earnings Per Share (Topic 260); Distinguishing Liabilities from Equity (Topic 480); Derivatives and Hedging (Topic 815): (Part 1) Accounting for Certain Financial Instruments with Down Round Features, (Part II) Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception” (“ASU 2017-11”). For freestanding equity-classified financial instruments, ASU 2017-11 requires entities that present earnings per share (EPS) in accordance with Topic 260 to recognize the effect of the down round feature when it is triggered. That effect is treated as a dividend and as a reduction of income available to common shareholders in basic EPS. Certain equity transactions following the issuance of the 2014 warrants have triggered anti-dilution clauses in the warrant agreements resulting in additional warrant shares and a reduction to the original strike price of the warrants. ASU 2017-11 prescribes a method to measure the value of a deemed dividend related to a triggering event by computing the difference in fair value between two instruments that have terms consistent with the actual instrument but that do not have a down round feature, where the number of warrant shares and strike price of one instrument corresponds to the actual instrument before the triggering event and the number of warrant shares and strike price of the other instrument corresponds to the actual instrument immediately after the triggering event. Following ASU 2017-11, for the years ending December 31, 2019 and December 31, 2018, the Company reduced its accumulated deficit by approximately $3,000 and $8,000 respectively related to triggering events.