Changes In Equity And Comprehensive Income (Summary Of Changes In Equity) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, beginning of period			$ 1,145.7	$ 1,150.8
Dividends			(39.3)	(38.5)
Exercise of stock options, net of shares reacquired			17.8	2.2
Stock compensation expense			11.1	11.4
Excess tax benefit from stock based compensation			0.0	(0.3)
Net income	$ 69.3	$ 68.4	132.6	123.6
Other comprehensive income (loss)	38.7	(13.1)	63.2	20.6
Comprehensive income	108.0	55.3	195.8	144.2
Balance, end of period	1,331.1	1,269.8	1,331.1	1,269.8
Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, beginning of period			1,133.8	1,139.4
Dividends			(39.3)	(38.5)
Exercise of stock options, net of shares reacquired			17.8	2.2
Stock compensation expense			11.1	11.4
Excess tax benefit from stock based compensation			0.0	(0.3)
Net income			132.3	123.3
Other comprehensive income (loss)			62.8	20.6
Comprehensive income			195.1	143.9
Balance, end of period	1,318.5	1,258.1	1,318.5	1,258.1
Noncontrolling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, beginning of period			11.9	11.4
Net income			0.3	0.3
Other comprehensive income (loss)			0.4	0.0
Comprehensive income				0.3
Balance, end of period	$ 12.6	$ 11.7	$ 12.6	$ 11.7