Consolidated Statements of Shareholders' Equity (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pension and postretirement liability adjustment, Tax	$ 22.2	$ 0.5	$ 1.1
Dividend per share	$ 1.12	$ 1.11	$ 1.07
Accounting Standards Update 2014-09 [Member]
Income Tax Expense (Benefit), Intraperiod Tax Allocation		$ 1.5

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

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