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, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale, Amortized Cost	$ 463,985	$ 448,161
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,055	1,088
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	11,576	7,337
Debt Securities, Available-for-sale	453,464	441,912
Corporate Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	202,194	148,996
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	701	298
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	5,406	2,847
Debt Securities, Available-for-sale	197,489	146,447
Collateralized Mortgage Backed Securities
Debt Securities, Available-for-sale, Amortized Cost	6,092	6,857
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	252	180
Debt Securities, Available-for-sale	5,840	6,677
US Treasury Securities
Debt Securities, Available-for-sale, Amortized Cost	63,231	85,510
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	423	396
Debt Securities, Available-for-sale	62,809	85,114
US Government Agencies Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	3	14
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Debt Securities, Available-for-sale	3	14
US Government-sponsored Enterprises Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	6,596	9,887
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	110	205
Debt Securities, Available-for-sale	6,486	9,682
US States and Political Subdivisions Debt Securities
Debt Securities, Available-for-sale, Amortized Cost	172,860	182,664
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	302	598
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	5,228	3,619
Debt Securities, Available-for-sale	167,934	179,643
Debt Security, Government, Non-US
Debt Securities, Available-for-sale, Amortized Cost	7,039	4,227
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	51	13
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	46	90
Debt Securities, Available-for-sale	7,044	4,150
Redeemable Preferred Stock
Debt Securities, Available-for-sale, Amortized Cost	5,970	10,006
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	179
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	111	0
Debt Securities, Available-for-sale	$ 5,859	$ 10,185

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=82897076&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
-Publisher FASB
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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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-Section 50
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Amount 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
-Topic 320
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