Consolidated Statements of Shareholders' Equity (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension and postretirement liability adjustment, tax	$ 1.1	$ 22.2	$ 0.5
Dividend per share (in dollars per shares)	$ 1.13	$ 1.12	$ 1.11
Cumulative effect of ASU 2014-09
Income tax expense (benefit), intraperiod tax allocation			$ 1.5
Cumulative effect of ASU 2016-13
Income tax expense (benefit), intraperiod tax allocation	$ 0.2

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

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