CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Stockholders' Equity [Abstract]
Cash dividends, per share	$ .87	$ .81	$ 0.77
Stock Issued During Period, Shares, Purchase of Assets	41,846	205,835	238,053
Stock issued pursuant to stock-based compensation	24,482	39,816	47,065

Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

No definition available.

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