Share-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2018

Deferred Compensation Arrangements [Abstract]

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

The fair value of each grant is estimated on the date of grant using the Black-Scholes option-pricing model with the following weighted average assumptions:

	2018	2017
Dividend yield	6.5%	5.3%
Expected volatility	19.4%	19.8%
Expected lives	2.9 years	2.9 years
Risk-free interest rate	2.39%	1.49%

Schedule of Stock Option Activity

The following table summarizes our outstanding stock options:

	Nine Months Ended
	September 30,
	2018		2017
Options outstanding January 1,	859,182		541,679
Options granted under 2012 Plan	560,000		495,000
Options exercised under 2012 Plan	(241,669	)	(155,829	)
Options forfeited under 2012 Plan	(30,001	)	(6,668	)
Options exercised under 2005 Plan	(6,668	)	(15,000	)
Options outstanding, September 30,	1,140,844		859,182
Exercisable at September 30,	697,490		465,831