Per Share Data (Details) - $ / shares	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Earnings Per Share [Abstract]
Convertible securities which would affect denominator in calculating basic and dilutive earnings per share (in shares)	0
Shares outstanding (in shares)	32,500
Strike price (in dollars per share)	$ 42.03
Weighted average common shares issued (in shares)	5,005,160	5,002,832
Average treasury stock shares (in shares)	(264,657)	(201,327)
Weighted average common shares and common stock equivalents used to calculate basic and diluted earnings per share (in shares)	4,740,503	4,801,505