Condensed Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Capital in Excess of Par Value	Accumulated Income	Treasury Stock	Noncontrolling Interests
Balance at beginning of period (shares) at Dec. 31, 2020		99.4
Balance at beginning of period at Dec. 31, 2020	$ 1,970.0	$ 1.1	$ 2,326.6	$ (242.3)	$ (497.4)	$ 382.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	269.7			220.6		49.1
Receipt of treasury stock (shares)		(0.2)
Receipt of treasury stock	(16.4)				(16.4)
Dividends declared	(55.9)		(55.9)
Stock-based compensation	14.8		14.8
Distributions declared	(45.4)					(45.4)
Capital contributions from consolidated affiliates	41.8					41.8
Other (shares)		0.3
Other	(2.5)		15.1		(4.2)	(13.4)
Balance at end of period (shares) at Jun. 30, 2021		99.5
Balance at end of period at Jun. 30, 2021	2,176.1	$ 1.1	2,300.6	(21.7)	(518.0)	414.1
Balance at beginning of period (shares) at Mar. 31, 2021		99.6
Balance at beginning of period at Mar. 31, 2021	2,043.0	$ 1.1	2,302.7	(135.0)	(513.7)	387.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	139.3			113.3		26.0
Receipt of treasury stock	(0.8)				(0.8)
Dividends declared	(28.1)		(28.1)
Stock-based compensation	12.0		12.0
Distributions declared	(23.0)					(23.0)
Capital contributions from consolidated affiliates	36.0					36.0
Other (shares)		(0.1)
Other	(2.3)		14.0		(3.5)	(12.8)
Balance at end of period (shares) at Jun. 30, 2021		99.5
Balance at end of period at Jun. 30, 2021	2,176.1	$ 1.1	2,300.6	(21.7)	(518.0)	414.1
Balance at beginning of period (shares) at Dec. 31, 2021		99.5
Balance at beginning of period at Dec. 31, 2021	2,357.0	$ 1.1	2,289.6	141.8	(521.2)	445.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	178.0			136.2		41.8
Receipt of treasury stock (shares)		(0.1)
Receipt of treasury stock	(7.7)				(7.7)
Dividends declared	(56.1)			(56.1)
Stock-based compensation	16.3		16.3
Distributions declared	(45.4)					(45.4)
Capital contributions from consolidated affiliates	44.2					44.2
Other (shares)		0.4
Other	15.0		4.9		(1.9)	12.0
Balance at end of period (shares) at Jun. 30, 2022		99.8
Balance at end of period at Jun. 30, 2022	2,501.3	$ 1.1	2,310.8	221.9	(530.8)	498.3
Balance at beginning of period (shares) at Mar. 31, 2022		99.8
Balance at beginning of period at Mar. 31, 2022	2,448.4	$ 1.1	2,301.1	201.2	(529.9)	474.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	69.8			48.7		21.1
Receipt of treasury stock	(0.1)				(0.1)
Dividends declared	(28.0)			(28.0)
Stock-based compensation	8.8		8.8
Distributions declared	(20.5)					(20.5)
Capital contributions from consolidated affiliates	22.8					22.8
Other	0.1		0.9		(0.8)
Balance at end of period (shares) at Jun. 30, 2022		99.8
Balance at end of period at Jun. 30, 2022	$ 2,501.3	$ 1.1	$ 2,310.8	$ 221.9	$ (530.8)	$ 498.3