Fair Value Measurements (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Assets:
Total assets		$ 9,864
Liabilities:
Total liabilities	$ 15,058	39,126
Royalty obligation embedded derivative [Member]
Liabilities:
Derivative fair value of derivative liability		21,912
Rochester Royalty Obligation [Member]
Liabilities:
Derivative fair value of derivative liability		15,370
Other Derivative Instrument [Member]
Liabilities:
Derivative fair value of derivative liability	508	805
Gold Put Purchase and Call Sold Options Net [Member]
Liabilities:
Derivative fair value of derivative liability		1,039
Short-term Deposit [Member]
Assets:
Short-term deposits		5,982
Equity Securities [Member]
Assets:
Restricted certificates of deposits	2,766	3,882
Fair Value, Inputs, Level 1 [Member]
Assets:
Total assets		4,603
Liabilities:
Total liabilities	0	0
Fair Value, Inputs, Level 1 [Member] | Royalty obligation embedded derivative [Member]
Liabilities:
Derivative fair value of derivative liability		0
Fair Value, Inputs, Level 1 [Member] | Rochester Royalty Obligation [Member]
Liabilities:
Derivative fair value of derivative liability		0
Fair Value, Inputs, Level 1 [Member] | Other Derivative Instrument [Member]
Liabilities:
Derivative fair value of derivative liability	0	0
Fair Value, Inputs, Level 1 [Member] | Gold Put Purchase and Call Sold Options Net [Member]
Liabilities:
Derivative fair value of derivative liability		0
Fair Value, Inputs, Level 1 [Member] | Short-term Deposit [Member]
Assets:
Short-term deposits		4,603
Fair Value, Inputs, Level 1 [Member] | Equity Securities [Member]
Assets:
Restricted certificates of deposits	2,756	0
Fair Value, Inputs, Level 2 [Member]
Assets:
Total assets		3,882
Liabilities:
Total liabilities	508	1,844
Fair Value, Inputs, Level 2 [Member] | Royalty obligation embedded derivative [Member]
Liabilities:
Derivative fair value of derivative liability		0
Fair Value, Inputs, Level 2 [Member] | Rochester Royalty Obligation [Member]
Liabilities:
Derivative fair value of derivative liability		0
Fair Value, Inputs, Level 2 [Member] | Other Derivative Instrument [Member]
Liabilities:
Derivative fair value of derivative liability	508	805
Fair Value, Inputs, Level 2 [Member] | Gold Put Purchase and Call Sold Options Net [Member]
Liabilities:
Derivative fair value of derivative liability		1,039
Fair Value, Inputs, Level 2 [Member] | Short-term Deposit [Member]
Assets:
Short-term deposits		0
Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member]
Assets:
Restricted certificates of deposits	0	3,882
Fair Value, Inputs, Level 3 [Member]
Assets:
Total assets		1,379
Liabilities:
Total liabilities	14,550	37,282
Fair Value, Inputs, Level 3 [Member] | Royalty obligation embedded derivative [Member]
Liabilities:
Derivative fair value of derivative liability		21,912
Fair Value, Inputs, Level 3 [Member] | Rochester Royalty Obligation [Member]
Liabilities:
Derivative fair value of derivative liability		15,370
Fair Value, Inputs, Level 3 [Member] | Other Derivative Instrument [Member]
Liabilities:
Derivative fair value of derivative liability	0	0
Fair Value, Inputs, Level 3 [Member] | Gold Put Purchase and Call Sold Options Net [Member]
Liabilities:
Derivative fair value of derivative liability		0
Fair Value, Inputs, Level 3 [Member] | Short-term Deposit [Member]
Assets:
Short-term deposits		1,379
Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member]
Assets:
Restricted certificates of deposits	10	0
Equity Securities [Member]
Liabilities:
Balance at the beginning of the period	1,379	0
Additions		69
Revaluation		(55)
Settlements		0
Transfers from Level 1		1,365
Balance at the end of the period		1,379
Palmarejo Royalty Obligation [Member]
Liabilities:
Balance at the beginning of the period	21,912	40,338
Additions		0
Revaluation	(3,101)	2,001
Settlements	(13,854)	(20,427)
Transfers from Level 1		0
Balance at the end of the period	4,957	21,912
Palmarejo Royalty Obligation [Member] | Royalty obligation embedded derivative [Member]
Liabilities:
Derivative fair value of derivative liability	4,957
Palmarejo Royalty Obligation [Member] | Fair Value, Inputs, Level 1 [Member] | Royalty obligation embedded derivative [Member]
Liabilities:
Derivative fair value of derivative liability	0
Palmarejo Royalty Obligation [Member] | Fair Value, Inputs, Level 2 [Member] | Royalty obligation embedded derivative [Member]
Liabilities:
Derivative fair value of derivative liability	0
Palmarejo Royalty Obligation [Member] | Fair Value, Inputs, Level 3 [Member] | Royalty obligation embedded derivative [Member]
Liabilities:
Derivative fair value of derivative liability	4,957
Rochester Royalty Obligation [Member]
Liabilities:
Balance at the beginning of the period	15,370	21,630
Additions		0
Revaluation	(818)	(3,653)
Settlements	(4,959)	(2,607)
Transfers from Level 1		0
Balance at the end of the period	9,593	$ 15,370
Rochester Royalty Obligation [Member] | Royalty Obligation [Member]
Liabilities:
Derivative fair value of derivative liability	9,593
Rochester Royalty Obligation [Member] | Fair Value, Inputs, Level 1 [Member] | Royalty Obligation [Member]
Liabilities:
Derivative fair value of derivative liability	0
Rochester Royalty Obligation [Member] | Fair Value, Inputs, Level 2 [Member] | Royalty Obligation [Member]
Liabilities:
Derivative fair value of derivative liability	0
Rochester Royalty Obligation [Member] | Fair Value, Inputs, Level 3 [Member] | Royalty Obligation [Member]
Liabilities:
Derivative fair value of derivative liability	$ 9,593