Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Balance held at close of period in number of shares.

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Amount of realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI).

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The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Total number marketable securities sold during the period.

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Short-term and Other Investments - Summary (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Other Investments
Proceeds from Sale and Maturity of Marketable Securities		$ 300
Other investments, at fair value	$ 263		$ 293
Midas Gold Shares [Member]
Other Investments
Number Marketable Securities Sold	0	642,000
Proceeds from Sale and Maturity of Marketable Securities		$ 300
Marketable Securities, Realized Gain (Loss)		$ 15
Nusantara Resources
Other Investments
Shares owned	1,333,334		1,333,334