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	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale, Amortized Cost	$ 383,425	$ 463,985
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,827	1,055
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	2,278	11,576
Debt Securities, Available-for-sale	384,974	453,464
Corporate Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	161,369	202,194
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,832	701
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	1,178	5,406
Debt Securities, Available-for-sale	162,023	197,489
Collateralized Mortgage Backed Securities
Debt Securities, Available-for-sale, Amortized Cost	5,328	6,092
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	54	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	252
Debt Securities, Available-for-sale	5,382	5,840
US Treasury Securities
Debt Securities, Available-for-sale, Amortized Cost	50,340	63,231
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	257	1
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	48	423
Debt Securities, Available-for-sale	50,549	62,809
US Government-sponsored Enterprises Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	6,230	6,596
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	107	110
Debt Securities, Available-for-sale	6,123	6,486
US States and Political Subdivisions Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	153,439	172,860
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,512	302
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	943	5,228
Debt Securities, Available-for-sale	154,008	167,934
Debt Security, Government, Non-US
Debt Securities, Available-for-sale, Amortized Cost	6,719	7,039
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	172	51
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	2	46
Debt Securities, Available-for-sale	$ 6,889	7,044
US Government Agencies Debt Securities
Debt Securities, Available-for-sale, Amortized Cost		3
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax		0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax		0
Debt Securities, Available-for-sale		3
Redeemable Preferred Stock
Debt Securities, Available-for-sale, Amortized Cost		5,970
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax		0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax		111
Debt Securities, Available-for-sale		$ 5,859

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
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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