Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Common stock issued in acquisition, shares			1,873,879
Exercise of stock options, shares, including tax benefit		34,250	40,000
Purchase of treasury stock, shares	51,052	100,000
Reissue of treasury stock, shares	6,766	6,986	6,497
Cash dividends declared, per share	$ 0.66	$ 0.66	$ 0.66
Additional Paid-In Capital [Member]
Common stock issued in acquisition, shares			1,873,879
Restricted stock award grants, shares	48,300	35,400	31,500
Exercise of stock options, shares, including tax benefit		34,250	40,000
Reissue of treasury stock, shares	6,766	6,986	6,497
Retained Earnings [Member]
Cash dividends declared, per share	$ 0.66	$ 0.66	$ 0.66
Treasury Stock [Member]
Restricted stock award grants, shares	48,300	35,400	31,500
Exercise of stock options, shares, including tax benefit		34,250	40,000
Purchase of treasury stock, shares	51,052	100,000
Reissue of treasury stock, shares	6,766	6,986	6,497