Employee Stock Compensation Plans	3 Months Ended
Mar. 31, 2019
Share-based Payment Arrangement [Abstract]
Employee Stock Compensation Plans	9. Employee Stock Compensation Plans On June 18, 2013, Solitario’s shareholders approved the 2013 Solitario Exploration & Royalty Corp. Omnibus Stock and Incentive Plan (the “2013 Plan”). Under the terms of the 2013 Plan, a total of 1,750,000 shares of Solitario common stock were reserved for awards to directors, officers, employees and consultants. On June 29, 2017, Solitario shareholders approved an amendment to the 2013 Plan, which increased the number of shares of common stock available for issuance under the 2013 Plan from 1,750,000 to 5,750,000. Awards granted under the 2013 Plan may take the form of stock options, stock appreciation rights, restricted stock, and restricted stock units. The terms and conditions of the awards are pursuant to the 2013 Plan and are granted by the Board of Directors or a committee appointed by the Board of Directors. As of March 31, 2019, and December 31, 2018 there were options outstanding that are exercisable to acquire 4,373,000 and 5,223,160 shares, respectively, of Solitario common stock, with option prices between $0.28 and $0.77 per share. During the three months ended March 31, 2019, Solitario granted options exercisable into 150,000 shares of common stock, with an exercise price of $0.28 per share, a five-year term, and a grant date fair value of $23,000 based upon a Black-Scholes model, with a 64% volatility and a 2.4% risk-free interest rate. In addition, during the three months ended March 31, 2019, options exercisable into 1,000,160 shares of common stock, with exercise prices between $1.68 and $0.70 per share, expired unexercised. During the three months ended March 31, 2018, Solitario granted options exercisable into 100,000 shares to a consultant, with an exercise price of $0.62 per share, a seven-month term and a grant date fair value of $12,000 based upon a Black-Scholes model with a 66% volatility and a 1% risk-free interest rate. There were no exercises of options under the 2013 Plan during the three months ended March 31, 2019 and 2018. During the three months ended March 31, 2019 and 2018, Solitario recorded stock option compensation expense of $88,000 and $10,000. At March 31, 2019, the total unrecognized stock option compensation cost related to non-vested options is $572,000 and is expected to be recognized over a weighted average period of 22 months.

Employee Stock Compensation Plans

3 Months Ended

Mar. 31, 2019

Share-based Payment Arrangement [Abstract]

9. Employee Stock Compensation Plans

On June 18, 2013, Solitario’s shareholders approved the 2013 Solitario Exploration & Royalty Corp. Omnibus Stock and Incentive Plan (the “2013 Plan”). Under the terms of the 2013 Plan, a total of 1,750,000 shares of Solitario common stock were reserved for awards to directors, officers, employees and consultants. On June 29, 2017, Solitario shareholders approved an amendment to the 2013 Plan, which increased the number of shares of common stock available for issuance under the 2013 Plan from 1,750,000 to 5,750,000. Awards granted under the 2013 Plan may take the form of stock options, stock appreciation rights, restricted stock, and restricted stock units. The terms and conditions of the awards are pursuant to the 2013 Plan and are granted by the Board of Directors or a committee appointed by the Board of Directors.

As of March 31, 2019, and December 31, 2018 there were options outstanding that are exercisable to acquire 4,373,000 and 5,223,160 shares, respectively, of Solitario common stock, with option prices between $0.28 and $0.77 per share. During the three months ended March 31, 2019, Solitario granted options exercisable into 150,000 shares of common stock, with an exercise price of $0.28 per share, a five-year term, and a grant date fair value of $23,000 based upon a Black-Scholes model, with a 64% volatility and a 2.4% risk-free interest rate. In addition, during the three months ended March 31, 2019, options exercisable into 1,000,160 shares of common stock, with exercise prices between $1.68 and $0.70 per share, expired unexercised. During the three months ended March 31, 2018, Solitario granted options exercisable into 100,000 shares to a consultant, with an exercise price of $0.62 per share, a seven-month term and a grant date fair value of $12,000 based upon a Black-Scholes model with a 66% volatility and a 1% risk-free interest rate. There were no exercises of options under the 2013 Plan during the three months ended March 31, 2019 and 2018. During the three months ended March 31, 2019 and 2018, Solitario recorded stock option compensation expense of $88,000 and $10,000. At March 31, 2019, the total unrecognized stock option compensation cost related to non-vested options is $572,000 and is expected to be recognized over a weighted average period of 22 months.