Changes In Equity And Comprehensive Income (Summary Of Changes In Equity) (Detail) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2016	Jun. 30, 2015
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, beginning of period		$ 1,091.8	$ 1,070.6	$ 1,150.8	$ 1,070.6
Dividends			(38.3)	(38.5)
Reacquisition on open market			(25.0)	0.0
Exercise of stock options, net of shares reacquired			7.0	2.2
Stock compensation expense			10.8	11.4
Excess tax benefit from stock based compensation			(0.2)	(0.3)
Net income	$ 68.4	55.9	107.2	123.6	107.2
Other comprehensive income (loss)	(13.1)	28.6	(40.3)	20.6	(40.3)
Comprehensive income	55.3	84.5	66.9	144.2	66.9
Balance, end of period	1,269.8		1,091.8	1,269.8
Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, beginning of period		1,080.7	1,059.8	1,139.4	1,059.8
Dividends			(38.3)	(38.5)
Reacquisition on open market			(25.0)	0.0
Exercise of stock options, net of shares reacquired			7.0	2.2
Stock compensation expense			10.8	11.4
Excess tax benefit from stock based compensation			(0.2)	(0.3)
Net income			106.8	123.3
Other comprehensive income (loss)			(40.2)	20.6
Comprehensive income			66.6	143.9
Balance, end of period	1,258.1		1,080.7	1,258.1
Noncontrolling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, beginning of period		$ 11.1	10.8	11.4	$ 10.8
Net income			0.4	0.3
Other comprehensive income (loss)			(0.1)	0.0
Comprehensive income			0.3
Balance, end of period	$ 11.7		$ 11.1	$ 11.7