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

Income Taxes (Income Before Income Tax Provision) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Operating Loss Carryforwards [Line Items]
Net income (loss) before provision for income taxes	$ 1,363	$ (1,484)	$ 4,240	$ (500)
U.S.
Operating Loss Carryforwards [Line Items]
Net income (loss) before provision for income taxes	1,355	(1,498)	4,214	(528)
Foreign
Operating Loss Carryforwards [Line Items]
Net income (loss) before provision for income taxes	$ 8	$ 14	$ 26	$ 28