A-Mark Precious Metals, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity (Options Outstanding, Range of Exercise Prices and Other Details) (Details)

Stockholders' Equity (Options Outstanding, Range of Exercise Prices and Other Details) (Details) (USD $)	3 Months Ended
	Sep. 30, 2014	Jun. 30, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock options, Number of Shares Outstanding	230,127	230,787
Stock options outstanding, Weighted Average Remaining Contractual Life (years)	8 years 15 days
Stock options outstanding, Weighted Average Exercise Price (in dollars per share)	$ 9.89	$ 10.00
Stock options, Number of Shares Exercisable	134,242
Stock options exercisable, Weighted Average Remaining Contractual Life (years)	8 years 7 days
Stock options exercisable, Weighted Average Exercise Price (in dollars per share)	$ 11.00
Price Range $0 - $10.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock options, Exercise Price Ranges, lower range limit	$ 0
Stock options, Exercise Price Ranges, upper range limit	$ 10
Stock options, Number of Shares Outstanding	134,239
Stock options outstanding, Weighted Average Remaining Contractual Life (years)	8 years 1 month 8 days
Stock options outstanding, Weighted Average Exercise Price (in dollars per share)	$ 8.39
Stock options, Number of Shares Exercisable	38,354
Stock options exercisable, Weighted Average Remaining Contractual Life (years)	8 years 2 months 4 days
Stock options exercisable, Weighted Average Exercise Price (in dollars per share)	$ 8.50
Price Range $10.01 - $15.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock options, Exercise Price Ranges, lower range limit	$ 10.01
Stock options, Exercise Price Ranges, upper range limit	$ 15
Stock options, Number of Shares Outstanding	95,888
Stock options outstanding, Weighted Average Remaining Contractual Life (years)	7 years 11 months 14 days
Stock options outstanding, Weighted Average Exercise Price (in dollars per share)	$ 12.00
Stock options, Number of Shares Exercisable	95,888
Stock options exercisable, Weighted Average Remaining Contractual Life (years)	7 years 11 months 14 days
Stock options exercisable, Weighted Average Exercise Price (in dollars per share)	$ 12.00