Consolidated Statements of Equity (Parentheticals) - $ / shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Issue Stock for Directors, Employee Benefit and Stock Plans, related tax withholdings (in shares)	20,494	12,198	9,598
Dividends paid per common share (in dollars per share)	$ 0.89	$ 0.88	$ 0.85

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120397183&loc=d3e187085-122770

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Period Type:	duration