Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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+ Details

- Definition

Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

+ References

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+ Details

Impairment of Goodwill (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			12 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Goodwill
Carrying value of goodwill		$ 11,666			$ 11,666
Impairment of goodwill				11,666	58,489
Silver
Goodwill
Decrease in metal prices (as a percent)	34.00%
Gold
Goodwill
Decrease in metal prices (as a percent)	26.00%
Velardena Properties Asset Group
Goodwill
Carrying value of goodwill	500	11,700		0	11,700	70,200
Impairment of goodwill	$ 11,200	$ 1,300	$ 57,200		$ 58,500
Discount rate (as a percent)				21.00%	21.00%
Decrease in metal prices (as a percent)		20.00%	20.00%
Period of operating plan					25 years
Velardena Properties Asset Group \| Maximum \| Expected results
Goodwill
Plant throughput up to which company plans to ramp up production by 2015 (in tonnes per day)		1,150			1,150
Velardena Properties Asset Group \| Silver \| Maximum
Goodwill
Metal prices used in analysis (in dollars per ounce)				23.80
Velardena Properties Asset Group \| Silver \| Maximum \| Expected results
Goodwill
Metal prices used in analysis (in dollars per ounce)		34.78			34.78
Velardena Properties Asset Group \| Silver \| Minimum
Goodwill
Metal prices used in analysis (in dollars per ounce)				18.06
Velardena Properties Asset Group \| Silver \| Minimum \| Expected results
Goodwill
Metal prices used in analysis (in dollars per ounce)		23.77			23.77
Velardena Properties Asset Group \| Gold \| Maximum
Goodwill
Metal prices used in analysis (in dollars per ounce)				1,440
Velardena Properties Asset Group \| Gold \| Maximum \| Expected results
Goodwill
Metal prices used in analysis (in dollars per ounce)		1,866			1,866
Velardena Properties Asset Group \| Gold \| Minimum
Goodwill
Metal prices used in analysis (in dollars per ounce)				1,198
Velardena Properties Asset Group \| Gold \| Minimum \| Expected results
Goodwill
Metal prices used in analysis (in dollars per ounce)		1,394			1,394