Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Details
Available-for-sale Securities, Gross Realized Gains	$ 246	$ 973
Available-for-sale Securities, Gross Realized Losses	$ 75	$ 776

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

No definition available.

Name:	us-gaap_AvailableForSaleSecuritiesGrossRealizedGains
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration