2. Trading Securities (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Cost	$ 105,938	$ 111,386
Gross unrealized gain		354
Gross unrealized loss		(757)
Fair value	99,433	110,983
Trading securities - Debt [Member]
Cost	89,322	93,712
Gross unrealized gain	24	143
Gross unrealized loss	(383)	(12)
Fair value	88,963	93,843
Trading securities - Equity [Member]
Cost	16,616	17,674
Gross unrealized gain	96	211
Gross unrealized loss	(6,242)	(745)
Fair value	$ 10,470	$ 17,140

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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