Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]: Realized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Details
Debt Securities, Available-for-sale, Realized Gain (Loss), Excluding Other-than-temporary Impairment	$ 72	$ 1,271	$ 1,142	$ 1,249
Debt and Equity Securities, Realized Gain (Loss), Excluding Other-than-temporary Impairment	72	1,271	1,142	1,249
Equity Securities, FV-NI, Unrealized Gain (Loss)	490	184	(297)	377
Debt and Equity Securities, Gain (Loss)	562	1,455	845	1,626
Gain (Loss) on Sale of Other Investments	13	0	18	0
Gain (Loss) on Investments	$ 575	$ 1,455	$ 863	$ 1,626

Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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Amount of realized gain (loss) on investment in debt and equity securities. Excludes other-than-temporary impairment (OTTI).

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), excluding other-than-temporary impairment (OTTI).

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

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Amount of realized and unrealized gain (loss) on investment.

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Amount of gain (loss) included in earnings for investments classified as other.

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