Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Details
Available-for-sale Securities, Gross Realized Gains	$ 130	$ 780	$ 449	$ 2,119
Available-for-sale Securities, Gross Realized Losses	$ 377	$ 61	$ 891	$ 1,057

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.

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