Earnings Per Share Information (Tables)

12 Months Ended

Dec. 31, 2016

Earnings Per Share [Abstract]

Schedule of earnings per share calculation [Table Text Block]

Earnings per share is computed as follows:

	Year Ended December 31,
	2016		2015		2014
Income available to common shareholders:
Net income	$	22,284	$	21,798	$	23,169
Weighted-average shares:
Basic:
Outstanding	12,689,300		13,029,368		13,337,198
Partially-paid share subscriptions	416,720		436,081		484,025
Basic weighted-average shares	13,106,020		13,465,449		13,821,223
Diluted:
Basic from above	13,106,020		13,465,449		13,821,223
Incremental shares from assumed:
Exercise of stock subscription purchase rights	71,373		67,714		54,824
Exercise of stock options and awards	446,284		444,127		362,229
Diluted weighted-average shares	13,623,677		13,977,290		14,238,276
Share data:
Earnings per share--basic	$	1.70	$	1.62	$	1.68
Earnings per share--diluted	$	1.64	$	1.56	$	1.63