CONSOLIDATED STATEMENTS OF EQUITY (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Stockholders' Equity [Abstract]
Tax benefit (expense) on change in retirement obligations, tax	$ 5.3	$ 0.1	$ 1.6
Tax benefit from change on derivatives designated as cash flow hedges, tax	$ 0.8	$ 1.4	$ 1.4
Issuance of common stock from issuance of unvested shares, exercise of stock options and deferred compensation plans (in shares)	258,875	688,563	696,133
Repurchase of common stock (in shares)	0	876,423	388,953
Deferred compensation plan, tax	$ 3.1	$ 5.0	$ 5.5
Cash dividends declared, per common share outstanding (in dollars per share)	$ 2.16	$ 2.00	$ 2.00
Net income	$ 449.4	$ 377.8	$ 425.5