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	Sep. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale, Amortized Cost	$ 435,730	$ 463,985
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	6,583	1,055
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	2,024	11,576
Debt Securities, Available-for-sale	440,289	453,464
Corporate Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	205,770	202,194
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,326	701
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	1,107	5,406
Debt Securities, Available-for-sale	207,989	197,489
Collateralized Mortgage Backed Securities
Debt Securities, Available-for-sale, Amortized Cost	5,522	6,092
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	49	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	252
Debt Securities, Available-for-sale	5,571	5,840
US Treasury Securities
Debt Securities, Available-for-sale, Amortized Cost	39,852	63,231
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	294	1
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	69	423
Debt Securities, Available-for-sale	40,077	62,809
US Government-sponsored Enterprises Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	6,323	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	114	110
Debt Securities, Available-for-sale	6,209	6,486
US States and Political Subdivisions Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	165,493	172,860
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	2,552	302
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	731	5,228
Debt Securities, Available-for-sale	167,314	167,934
Debt Security, Government, Non-US
Debt Securities, Available-for-sale, Amortized Cost	6,800	7,039
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	165	51
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	3	46
Debt Securities, Available-for-sale	6,962	7,044
Redeemable Preferred Stock
Debt Securities, Available-for-sale, Amortized Cost	5,970	5,970
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	197	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	111
Debt Securities, Available-for-sale	$ 6,167	5,859
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

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)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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