Fair Value Disclosures [Text Block]: Fair Value, Assets Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Available-for-sale Securities, Debt Securities	$ 434,545	$ 449,487
Available-for-sale Securities, Equity Securities	5,455	5,333
Trading Securities	520	592
Corporate Debt Securities
Available-for-sale Securities, Debt Securities	170,903	187,695
Residential Mortgage Backed Securities
Available-for-sale Securities, Debt Securities	7,082	5,913
US Treasury Securities
Available-for-sale Securities, Debt Securities	43,868	43,109
US Government Agencies Debt Securities
Available-for-sale Securities, Debt Securities	17	23
US Government-sponsored Enterprises Debt Securities
Available-for-sale Securities, Debt Securities	9,894	9,880
US States and Political Subdivisions Debt Securities
Available-for-sale Securities, Debt Securities	188,507	186,811
Foreign Government Debt
Available-for-sale Securities, Debt Securities	4,264	4,954
Redeemable Preferred Stock
Available-for-sale Securities, Debt Securities	10,010	11,102
Common Stock
Available-for-sale Securities, Equity Securities	1,781	1,790
Nonredeemable Preferred Stock
Available-for-sale Securities, Equity Securities	3,674	3,543
Fair Value, Measurements, Recurring
Available-for-sale Securities, Debt Securities	434,545	449,487
Available-for-sale Securities, Equity Securities	5,455	5,333
Trading Securities	520	592
Assets, Fair Value Disclosure, Recurring	440,520	455,412
Fair Value, Measurements, Recurring | Corporate Debt Securities
Available-for-sale Securities, Debt Securities	170,903	187,695
Fair Value, Measurements, Recurring | Residential Mortgage Backed Securities
Available-for-sale Securities, Debt Securities	7,082	5,913
Fair Value, Measurements, Recurring | US Treasury Securities
Available-for-sale Securities, Debt Securities	43,868	43,109
Fair Value, Measurements, Recurring | US Government Agencies Debt Securities
Available-for-sale Securities, Debt Securities	17	23
Fair Value, Measurements, Recurring | US Government-sponsored Enterprises Debt Securities
Available-for-sale Securities, Debt Securities	9,894	9,880
Fair Value, Measurements, Recurring | US States and Political Subdivisions Debt Securities
Available-for-sale Securities, Debt Securities	188,507	186,811
Fair Value, Measurements, Recurring | Foreign Government Debt
Available-for-sale Securities, Debt Securities	4,264	4,954
Fair Value, Measurements, Recurring | Redeemable Preferred Stock
Available-for-sale Securities, Debt Securities	10,010	11,102
Fair Value, Measurements, Recurring | Common Stock
Available-for-sale Securities, Equity Securities	1,781	1,790
Fair Value, Measurements, Recurring | Nonredeemable Preferred Stock
Available-for-sale Securities, Equity Securities	3,674	3,543
Fair Value, Measurements, Recurring | Equity Securities
Trading Securities	520	592
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring
Available-for-sale Securities, Debt Securities	10,010	11,102
Available-for-sale Securities, Equity Securities	5,455	5,333
Trading Securities	520	592
Assets, Fair Value Disclosure, Recurring	15,985	17,027
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | Corporate Debt Securities
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | Residential Mortgage Backed Securities
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | US Treasury Securities
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | US Government Agencies Debt Securities
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | US Government-sponsored Enterprises Debt Securities
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | US States and Political Subdivisions Debt Securities
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | Foreign Government Debt
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | Redeemable Preferred Stock
Available-for-sale Securities, Debt Securities	10,010	11,102
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | Common Stock
Available-for-sale Securities, Equity Securities	1,781	1,790
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | Nonredeemable Preferred Stock
Available-for-sale Securities, Equity Securities	3,674	3,543
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring | Equity Securities
Trading Securities	520	592
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring
Available-for-sale Securities, Debt Securities	422,579	436,352
Available-for-sale Securities, Equity Securities	0	0
Trading Securities	0	0
Assets, Fair Value Disclosure, Recurring	422,579	436,352
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring | Corporate Debt Securities
Available-for-sale Securities, Debt Securities	170,903	187,695
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring | Residential Mortgage Backed Securities
Available-for-sale Securities, Debt Securities	7,082	5,913
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring | US Treasury Securities
Available-for-sale Securities, Debt Securities	43,868	43,109
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring | US Government Agencies Debt Securities
Available-for-sale Securities, Debt Securities	17	23
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring | US Government-sponsored Enterprises Debt Securities
Available-for-sale Securities, Debt Securities	9,894	9,880
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring | US States and Political Subdivisions Debt Securities
Available-for-sale Securities, Debt Securities	186,551	184,778
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring | Foreign Government Debt
Available-for-sale Securities, Debt Securities	4,264	4,954
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring | Redeemable Preferred Stock
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring | Common Stock
Available-for-sale Securities, Equity Securities	0	0
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring | Nonredeemable Preferred Stock
Available-for-sale Securities, Equity Securities	0	0
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring | Equity Securities
Trading Securities	0	0
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring
Available-for-sale Securities, Debt Securities	1,956	2,033
Available-for-sale Securities, Equity Securities	0	0
Trading Securities	0	0
Assets, Fair Value Disclosure, Recurring	1,956	2,033
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | Corporate Debt Securities
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | Residential Mortgage Backed Securities
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | US Treasury Securities
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | US Government Agencies Debt Securities
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | US Government-sponsored Enterprises Debt Securities
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | US States and Political Subdivisions Debt Securities
Available-for-sale Securities, Debt Securities	1,956	2,033
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | Foreign Government Debt
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | Redeemable Preferred Stock
Available-for-sale Securities, Debt Securities	0	0
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | Common Stock
Available-for-sale Securities, Equity Securities	0	0
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | Nonredeemable Preferred Stock
Available-for-sale Securities, Equity Securities	0	0
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | Equity Securities
Trading Securities	$ 0	$ 0