Statements of Operations of Discontinued Operations (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Revenues	$ 0.7	$ 39.8	$ 37.8
Cost of sales	0.4	25.3	23.4
Gross profit	0.3	14.5	14.4
Selling, general and administrative expenses	0.5	6.5	6.9
Amortization of intangibles		1.1	1.6
Operating profit (loss)	(0.2)	6.9	5.9
Nonoperating income	(51.0)	(0.1)	(8.8)
Earnings before income taxes	44.5	9.2	6.7
Income tax expense	19.6	3.7	2.5
Earnings from discontinued operations, net of income taxes	24.9	5.5	4.2
Discontinued Operations
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Nonoperating income	$ 44.7	$ 2.3	$ 0.8