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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES : Trading Securities (Details) - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Short-term Investments	$ 22,539		$ 111,386
Available-for-sale Securities, Gross Unrealized Gain		$ 1,914	354
Available-for-sale Securities, Gross Unrealized Loss		$ (4,756)	(757)
Investment Owned, at Fair Value	19,697		110,983
Trading Securites Other Equity [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Short-term Investments	22,539
Available-for-sale Securities, Gross Unrealized Gain	1,914
Available-for-sale Securities, Gross Unrealized Loss	(4,756)
Investment Owned, at Fair Value	$ 19,697
Trading Securites Debt [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Short-term Investments			93,712
Available-for-sale Securities, Gross Unrealized Gain			143
Available-for-sale Securities, Gross Unrealized Loss			(12)
Investment Owned, at Fair Value			93,843
Trading Securites Equity [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Short-term Investments			17,674
Available-for-sale Securities, Gross Unrealized Gain			211
Available-for-sale Securities, Gross Unrealized Loss			(745)
Investment Owned, at Fair Value			$ 17,140