Changes In Equity And Comprehensive Income (Classification Of Accumulated Other Comprehensive Income Reflected On Consolidated Balance Sheets) (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, beginning balance	$ (380.1)
Other comprehensive income (loss) before reclassifications	32.4
Amounts reclassified from accumulated other comprehensive income	2.6
Net current-period othre comprehensive income (loss)	35.0
Accumulated other comprehensive loss, ending balance	(345.1)
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, beginning balance	(292.1)
Other comprehensive income (loss) before reclassifications	7.0
Net current-period othre comprehensive income (loss)	9.6
Accumulated other comprehensive loss, ending balance	(282.5)
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, beginning balance	(88.0)
Other comprehensive income (loss) before reclassifications	25.4
Amounts reclassified from accumulated other comprehensive income	0.0
Net current-period othre comprehensive income (loss)	25.4
Accumulated other comprehensive loss, ending balance	$ (62.6)