Consolidated Statements of Stockholders' Equity (Parentheticals) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
AOCI Attributable to Parent [Member]
Pension and OPEB adjustments, tax	$ 2.9	$ 3.4	$ 8.4
Change in fair value of derivatives, tax	$ 0.4	$ 0.3	$ 0.2
Retained Earnings [Member]
Dividends declared, per share (in dollars per share)	$ 0.70	$ 0.62	$ 0.54

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

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