Condensed Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	La Preciosa [Member]	La Preciosa [Member] Common Stock	La Preciosa [Member] Additional Paid-In Capital	La Preciosa [Member] Accumulated Deficit	La Preciosa [Member] Accumulated Other Comprehensive Income (Loss)	GRC [Member]	GRC [Member] Common Stock	GRC [Member] Additional Paid-In Capital	GRC [Member] Accumulated Deficit	GRC [Member] Accumulated Other Comprehensive Income (Loss)	Paramount Gold and Silver Corp. [Member]	Paramount Gold and Silver Corp. [Member] Common Stock	Paramount Gold and Silver Corp. [Member] Additional Paid-In Capital	Paramount Gold and Silver Corp. [Member] Accumulated Deficit	Paramount Gold and Silver Corp. [Member] Accumulated Other Comprehensive Income (Loss)
Balances at Dec. 31, 2012	$ 2,198,280	$ 903	$ 2,601,254	$ (396,156)	$ (7,721)
Balances, in shares at Dec. 31, 2012		90,342,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(650,563)	$ 0	0	(650,563)	0
Other comprehensive income (loss)	2,815	$ 0	0	0	2,815
Stock Repurchased During Period, Shares							(1,691,000)
Stock Repurchased During Period, Value						$ (27,552)	$ (17)	$ (27,535)	$ 0	$ 0
Common stock issued for the acquisition of Paramount Gold and Silver Corp. (in shares)							11,573,000					2,130,000
Common stock issued for the acquisition of Paramount Gold and Silver Corp.						$ 179,140	$ 116	$ 179,024	$ 0	$ 0	$ 22,198	$ 21	$ 22,177	$ 0	$ 0
Common stock issued under stock-based compensation plans, net (in shares)		489,000
Common stock issued under stock-based compensation plans, net	6,249	$ 5	6,244	0	0
Balances at Dec. 31, 2013	1,730,567	$ 1,028	2,781,164	(1,046,719)	(4,906)
Balances, in shares at Dec. 31, 2013		102,843,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(1,186,874)	$ 0	0	(1,186,874)	0
Other comprehensive income (loss)	2,098	$ 0	0	0	2,098
Common stock issued under stock-based compensation plans, net (in shares)		541,000
Common stock issued under stock-based compensation plans, net	8,537	$ 6	8,531	0	0
Balances at Dec. 31, 2014	554,328	$ 1,034	2,789,695	(2,233,593)	(2,808)
Balances, in shares at Dec. 31, 2014		103,384,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(367,183)	$ 0	0	(367,183)	0
Other comprehensive income (loss)	$ (914)	$ 0	0	0	(914)
Common stock issued for the acquisition of Paramount Gold and Silver Corp. (in shares)	32,667,327																32,667,000
Common stock issued for the acquisition of Paramount Gold and Silver Corp.																$ 188,817	$ 327	$ 188,490	$ 0	$ 0
Common stock issued for the extinguishment of Senior Notes (in shares)		14,365,000
Common stock issued for the extinguishment of Senior Notes	$ 38,523	$ 144	38,379	0	0
Common stock issued under stock-based compensation plans, net (in shares)		923,000
Common stock issued under stock-based compensation plans, net	7,905	$ 8	7,897	0	0
Balances at Dec. 31, 2015	$ 421,476	$ 1,513	$ 3,024,461	$ (2,600,776)	$ (3,722)
Balances, in shares at Dec. 31, 2015		151,339,000