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, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale, Amortized Cost	$ 458,503	$ 463,985
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	5,590	1,055
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	2,667	11,576
Debt Securities, Available-for-sale	461,426	453,464
Corporate Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	234,938	202,194
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,223	701
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	1,361	5,406
Debt Securities, Available-for-sale	236,800	197,489
Collateralized Mortgage Backed Securities
Debt Securities, Available-for-sale, Amortized Cost	5,745	6,092
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	10	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	3	252
Debt Securities, Available-for-sale	5,752	5,840
US Treasury Securities
Debt Securities, Available-for-sale, Amortized Cost	31,829	63,231
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	253	1
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	103	423
Debt Securities, Available-for-sale	31,979	62,809
US Government-sponsored Enterprises Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	6,414	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	111	110
Debt Securities, Available-for-sale	6,303	6,486
US States and Political Subdivisions Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	166,727	172,860
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,785	302
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	1,083	5,228
Debt Securities, Available-for-sale	167,429	167,934
Debt Security, Government, Non-US
Debt Securities, Available-for-sale, Amortized Cost	6,880	7,039
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	153	51
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	6	46
Debt Securities, Available-for-sale	7,027	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	166	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	111
Debt Securities, Available-for-sale	$ 6,136	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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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
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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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