3. Trading Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Trading securities, cost		$ 111,386
Gross unrealized gain	$ 74,099	354
Gross unrealized loss	(1,847)	(757)
Fair value of trading securities		110,983
Trading securities - Equity [Member]
Trading securities, cost	36,851	17,674
Gross unrealized gain		211
Gross unrealized loss		(745)
Fair value of trading securities	$ 109,103	17,140
Trading securities - Debt [Member]
Trading securities, cost		93,712
Gross unrealized gain		143
Gross unrealized loss		(12)
Fair value of trading securities		$ 93,843

Fair value of trading securities

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Paragraph 2
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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