Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Basic earnings per share computation [Abstract]
Net income applicable to common stock	$ 2,857	$ 3,368	$ 9,166	$ 9,909
Weighted average common shares outstanding (in shares)	3,011,687	3,035,214	3,019,202	3,038,973
Earnings per share - basic (in dollars per share)	$ 0.95	$ 1.11	$ 3.04	$ 3.26
Diluted earnings per share computation [Abstract]
Weighted average common shares outstanding for basic earnings per share (in shares)	3,011,687	3,035,214	3,019,202	3,038,973
Add: Dilutive effects of restricted stock (in shares)	1,464	1,486	1,468	1,427
Weighted average common shares outstanding for dilutive earnings per share (in shares)	3,013,151	3,036,700	3,020,670	3,040,400
Earnings per share - diluted (in dollars per share)	$ 0.95	$ 1.11	$ 3.03	$ 3.26
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive restricted stock excluded from net income per share calculations (in shares)	2,696	1,938	2,696	2,913
Restricted Stock [Member] | Minimum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive stock share price range (in dollars per share)	$ 44.50	$ 34.70	$ 44.50	$ 34.70
Restricted Stock [Member] | Maximum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive stock share price range (in dollars per share)	$ 53.15	$ 50.50	$ 53.15	$ 50.50