Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Fair value measurements
Short-term available for sale securities		$ 242
Recurring \| Level 1
Fair value measurements
Cash equivalents	19,146	44,406
Short-term available for sale securities		242
Trade accounts receivable	25	1,291
Assets	19,171	45,939
Recurring \| Total
Fair value measurements
Cash equivalents	19,146	44,406
Short-term available for sale securities		242
Trade accounts receivable	25	1,291
Assets	19,171	45,939
Non-recurring \| Level 3
Fair value measurements
Mineral properties	22,397	239,200
Exploration properties	2,993	15,685
Goodwill		11,666
Assets	25,390	266,551
Non-recurring \| Total
Fair value measurements
Mineral properties	22,397	239,200
Exploration properties	2,993	15,685
Goodwill		11,666
Assets	$ 25,390	$ 266,551

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef

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+ Details

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

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