CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Parenthetical) - $ / shares	3 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2018
Statement of Stockholders' Equity [Abstract]
Cash dividends (in dollars per share)	$ 0.23	$ 0.21	$ 0.19
Common stock (purchased) sold by directors' deferred compensation plan (in net shares)	14,600	14,100	2,850
Shares of common stock repurchased	213,700	269,885	344,362

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Period Type:	duration