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, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Details
Debt Securities, Available-for-sale, Realized Gain (Loss), Excluding Other-than-temporary Impairment	$ (366)	$ 146	$ (195)	$ 343
Equity Securities, FV-NI, Realized Gain (Loss)	(5)	0	(5)	0
Debt and Equity Securities, Realized Gain (Loss), Excluding Other-than-temporary Impairment	(371)	146	(200)	343
Equity Securities, FV-NI, Unrealized Gain (Loss)	(52)	(47)	(152)	(72)
Debt and Equity Securities, Gain (Loss)	(423)	99	(352)	271
Gain (Loss) on Sale of Other Investments	0	1	0	1
Gain (Loss) on Investments	$ (423)	$ 100	$ (352)	$ 272

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 realized gain (loss) from sale of 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 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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