Consolidated Statements of Shareholders' Equity (Parentheticals) - $ / shares	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Consolidated Statements of Shareholders' Equity (Parenthetical)
Tax withholdings for Directors, Employee Benefit and Stock Plans (in shares)	23,113	23,160	46,152
Dividends paid per Common Share (in dollars per share)	$ 0.81	$ 0.80	$ 0.78

Aggregate dividends paid during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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