Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]: Debt Securities, Available-for-sale [Table Text Block] (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale, Amortized Cost	$ 380,603	$ 383,425
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	7,703	3,827
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	4,061	2,278
Debt Securities, Available-for-sale	384,245	384,974
Corporate Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	134,543	161,369
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,204	1,832
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	3,002	1,178
Debt Securities, Available-for-sale	134,745	162,023
Collateralized Mortgage Backed Securities
Debt Securities, Available-for-sale, Amortized Cost	4,977	5,328
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	268	54
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Debt Securities, Available-for-sale	5,245	5,382
US Treasury Securities
Debt Securities, Available-for-sale, Amortized Cost	50,357	50,340
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,081	257
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	48
Debt Securities, Available-for-sale	51,438	50,549
US Government-sponsored Enterprises Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	6,043	6,230
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	229	107
Debt Securities, Available-for-sale	5,815	6,123
US States and Political Subdivisions Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	179,672	153,439
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	2,853	1,512
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	830	943
Debt Securities, Available-for-sale	181,695	154,008
Debt Security, Government, Non-US
Debt Securities, Available-for-sale, Amortized Cost	5,011	6,719
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	296	172
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	2
Debt Securities, Available-for-sale	$ 5,307	$ 6,889

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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