Credit Arrangements, Stock Buy-Back Program (Details)		3 Months Ended	12 Months Ended
	Jul. 22, 2016 USD ($) Note shares	Mar. 31, 2017 USD ($) shares	Dec. 31, 2017
STOCK REPURCHASE PROGRAM [Abstract]
Treasury stock, shares, acquired (in shares) | shares		1,500
Amount paid to repurchase shares during the year | $		$ 26,000
Stock Buy-Back Program [Member]
STOCK REPURCHASE PROGRAM [Abstract]
Treasury stock, shares, acquired (in shares) | shares	300,000
% of shares owned by shareholder	8.00%
Stock Buy-Back Program [Member] | Promissory Notes [Member]
STOCK REPURCHASE PROGRAM [Abstract]
Number of promissory notes issued | Note	2
Amount paid to repurchase shares during the year | $	$ 2,900,000
Debt Instrument, Interest Rate, Stated Percentage	2.00%
Stock Buy-Back Program [Member] | Promissory Notes [Member] | First Half of Note Value [Member]
STOCK REPURCHASE PROGRAM [Abstract]
Debt instrument, term			1 year
Stock Buy-Back Program [Member] | Promissory Notes [Member] | Second Half of Note Value [Member]
STOCK REPURCHASE PROGRAM [Abstract]
Debt instrument, term			2 years