Changes In Equity And Comprehensive Income (Classification Of Accumulated Other Comprehensive Income Reflected On Consolidated Balance Sheets) (Detail) $ in Millions	6 Months Ended
	Jun. 30, 2018 USD ($)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, beginning balance	$ (380.1)
Other comprehensive income (loss) before reclassifications	(12.0)
Amounts reclassified from accumulated other comprehensive income	4.8
Net current-period othre comprehensive income (loss)	(7.2)
Accumulated other comprehensive loss, ending balance	(387.3)
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	9.3
Net current-period othre comprehensive income (loss)	14.1
Accumulated other comprehensive loss, ending balance	(278.0)
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	(21.3)
Amounts reclassified from accumulated other comprehensive income	0.0
Net current-period othre comprehensive income (loss)	(21.3)
Accumulated other comprehensive loss, ending balance	$ (109.3)