Other Current and Non-Current Liabilities - Components of Other Current and Other Non-Current Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Other current liabilities:
Accrued salaries, wages and related costs	$ 194.0	$ 149.4
Accrued operating expenses(1)	237.2	156.8
Accrued customer volume rebates	87.9	76.1
Accrued interest	38.5	37.9
Accrued employee benefit liability	4.4	3.2
Total	562.0	423.4
Other non-current liabilities:
Accrued employee benefit liability	163.7	172.4
Other postretirement liability	46.1	51.7
Other various liabilities(1)	281.0	178.0
Total	490.8	$ 402.1
Accrued operating expenses, related tax liabilities	36.4
Accrued various expenses, related tax liabilities	$ 227.6