Description of Business and Summary of Significant Accounting Policies - Additional Information (Details) $ / shares in Units, $ in Millions		3 Months Ended	12 Months Ended
	Apr. 17, 2015 $ / shares shares	Sep. 30, 2015 USD ($) $ / shares	Jun. 30, 2015 $ / shares shares
Accounting Policies [Line Items]
Common stock, par value | $ / shares	$ 0.01	$ 0.01	$ 0.01
Concentration of credit risk uninsured cash amount | $		$ 8
Cash, Uninsured Amount, Commentary		We deposit our cash with financial institutions which we believe have sufficient credit quality to minimize the risk of loss
Common Stock
Accounting Policies [Line Items]
Capital issued for Spin-off transaction (in shares)			8,101,371
Spinoff
Accounting Policies [Line Items]
Stockholders equity, spinoff description		On the distribution date, stockholders of PGSC received one share of Company common stock for every twenty shares of PGSC common stock held.
Stockholders equity, spinoff conversion ratio	0.05
Spinoff | Common Stock
Accounting Policies [Line Items]
Capital issued for Spin-off transaction (in shares)	8,101,371
Paramount Gold and Silver Corp.
Accounting Policies [Line Items]
Parent's ownership interest		100.00%