v3.7.0.1
Equity, Dividends and Change in Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss Attributable to Stockholders, Net of Tax (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance $ 639.0 $ 524.9 $ 325.0
Other comprehensive income before reclassifications (26.5) (22.5) (32.1)
Reclassifications 0.2 0.4 0.2
Ending Balance 679.2 639.0 524.9
Foreign Currency Items [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance (52.0) (27.7) (3.8)
Other comprehensive income before reclassifications (21.7) (24.3) (23.9)
Ending Balance (73.7) (52.0) (27.7)
Defined Benefit Items [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance (5.4) (7.6) 0.4
Other comprehensive income before reclassifications (4.8) 1.8 (8.2)
Reclassifications 0.2 0.4 0.2
Ending Balance (10.0) (5.4) (7.6)
Total [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance (57.4) (35.3) (3.4)
Ending Balance (83.7) (57.4) (35.3)
Total Attributable to Noncontrolling Interest [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance (0.1) (0.1) (0.1)
Other comprehensive income before reclassifications (0.1)    
Ending Balance (0.2) (0.1) (0.1)
Total Attributable to Stockholders [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance (57.3) (35.2) (3.3)
Other comprehensive income before reclassifications (26.4) (22.5) (32.1)
Reclassifications 0.2 0.4 0.2
Ending Balance $ (83.5) $ (57.3) $ (35.2)