Financial Statements of Parent Company Guarantor - Condensed Consolidating Balance Sheet (Detail) - USD ($) $ in Millions	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 907.5		$ 113.3	$ 238.1	$ 238.5
Accounts and notes receivable, net	985.2	$ 838.1	831.6
Inventories	593.5	577.6	581.0
Other current assets	232.8	226.3	222.9
Total current assets	2,719.0		1,748.8
Property, plant and equipment, net	546.5		545.5
Other assets
Investments in subsidiaries	0.0		0.0
Goodwill	4,380.1		4,351.1
Intangibles, net	1,536.5		1,558.4
Long-term intercompany debt			0.0
Other non-current assets	186.0	183.4	429.9
Total other assets	6,102.6		6,339.4
Total assets	9,368.1		8,633.7
Current liabilities
Current maturities of long-term debt and short-term borrowings	0.2		0.0
Accounts payable	404.0		495.7
Employee compensation and benefits	142.7		186.6
Other current liabilities	480.6	523.6	517.1
Total current liabilities	1,027.5		1,199.4
Other liabilities
Long-term debt	2,673.1		1,440.7
Pension and other post-retirement compensation and benefits	291.9		285.6
Deferred tax liabilities	369.1	$ 364.6	394.8
Other non-current liabilities	286.8		275.4
Total liabilities	4,648.4		3,595.9
Equity
Total equity	4,719.7		5,037.8	4,374.8	4,254.4
Total liabilities and equity	9,368.1		8,633.7
Parent Company Guarantor
Current assets
Cash and cash equivalents	0.2		0.0	0.0	0.0
Accounts and notes receivable, net	0.0		0.0
Inventories	0.0		0.0
Other current assets	0.9		10.8
Total current assets	1.1		10.8
Property, plant and equipment, net	0.0		0.0
Other assets
Investments in subsidiaries	5,104.8		5,205.1
Goodwill	0.0		0.0
Intangibles, net	0.0		0.0
Long-term intercompany debt			0.0
Other non-current assets	2.2		2.2
Total other assets	5,107.0		5,207.3
Total assets	5,108.1		5,218.1
Current liabilities
Current maturities of long-term debt and short-term borrowings	0.0
Accounts payable	1.5		1.4
Employee compensation and benefits	0.4		0.4
Other current liabilities	69.8		99.6
Total current liabilities	71.7		101.4
Other liabilities
Long-term debt	286.5		48.4
Pension and other post-retirement compensation and benefits	0.0		0.0
Deferred tax liabilities	0.0		0.0
Other non-current liabilities	30.2		30.5
Total liabilities	388.4		180.3
Equity
Total equity	4,719.7		5,037.8
Total liabilities and equity	5,108.1		5,218.1
Guarantor Subsidiaries
Current assets
Cash and cash equivalents	0.0		0.0	0.0	0.0
Accounts and notes receivable, net	0.0		0.0
Inventories	0.0		0.0
Other current assets	0.2		1.8
Total current assets	0.2		1.8
Property, plant and equipment, net	0.0		0.0
Other assets
Investments in subsidiaries	5,009.0		5,109.6
Goodwill	0.0		0.0
Intangibles, net	0.0		0.0
Long-term intercompany debt			94.1
Other non-current assets	96.0		0.0
Total other assets	5,105.0		5,203.7
Total assets	5,105.2		5,205.5
Current liabilities
Current maturities of long-term debt and short-term borrowings	0.0
Accounts payable	0.0		0.0
Employee compensation and benefits	0.0		0.0
Other current liabilities	0.4		0.4
Total current liabilities	0.4		0.4
Other liabilities
Long-term debt	0.0		0.0
Pension and other post-retirement compensation and benefits	0.0		0.0
Deferred tax liabilities	0.0		0.0
Other non-current liabilities	0.0		0.0
Total liabilities	0.4		0.4
Equity
Total equity	5,104.8		5,205.1
Total liabilities and equity	5,105.2		5,205.5
Subsidiary Issuer
Current assets
Cash and cash equivalents	0.0		0.0	0.1	0.0
Accounts and notes receivable, net	0.0		0.0
Inventories	0.0		0.0
Other current assets	5.1		1.5
Total current assets	5.1		1.5
Property, plant and equipment, net	0.0		0.0
Other assets
Investments in subsidiaries	7,068.3		7,156.1
Goodwill	0.0		0.0
Intangibles, net	0.0		0.0
Long-term intercompany debt			614.0
Other non-current assets	870.6		0.0
Total other assets	7,938.9		7,770.1
Total assets	7,944.0		7,771.6
Current liabilities
Current maturities of long-term debt and short-term borrowings	0.0
Accounts payable	0.0		0.0
Employee compensation and benefits	0.0		0.0
Other current liabilities	12.5		9.4
Total current liabilities	12.5		9.4
Other liabilities
Long-term debt	2,922.7		2,652.8
Pension and other post-retirement compensation and benefits	0.0		0.0
Deferred tax liabilities	0.0		0.0
Other non-current liabilities	0.0		0.0
Total liabilities	2,935.2		2,662.2
Equity
Total equity	5,008.8		5,109.4
Total liabilities and equity	7,944.0		7,771.6
Non-Guarantor Subsidiaries
Current assets
Cash and cash equivalents	907.3		113.3	238.0	238.5
Accounts and notes receivable, net	985.2		831.6
Inventories	593.5		581.0
Other current assets	236.1		239.3
Total current assets	2,722.1		1,765.2
Property, plant and equipment, net	546.5		545.5
Other assets
Investments in subsidiaries	0.0		0.0
Goodwill	4,380.1		4,351.1
Intangibles, net	1,536.5		1,558.4
Long-term intercompany debt			(708.1)
Other non-current assets	1,283.4		2,317.1
Total other assets	7,200.0		7,518.5
Total assets	10,468.6		9,829.2
Current liabilities
Current maturities of long-term debt and short-term borrowings	0.2
Accounts payable	402.5		494.3
Employee compensation and benefits	142.3		186.2
Other current liabilities	407.4		438.2
Total current liabilities	952.4		1,118.7
Other liabilities
Long-term debt	1,530.1		628.9
Pension and other post-retirement compensation and benefits	291.9		285.6
Deferred tax liabilities	369.1		394.8
Other non-current liabilities	256.6		244.9
Total liabilities	3,400.1		2,672.9
Equity
Total equity	7,068.5		7,156.3
Total liabilities and equity	10,468.6		9,829.2
Consolidation, Eliminations
Current assets
Cash and cash equivalents	0.0		0.0	$ 0.0	$ 0.0
Accounts and notes receivable, net	0.0		0.0
Inventories	0.0		0.0
Other current assets	(9.5)		(30.5)
Total current assets	(9.5)		(30.5)
Property, plant and equipment, net	0.0		0.0
Other assets
Investments in subsidiaries	(17,182.1)		(17,470.8)
Goodwill	0.0		0.0
Intangibles, net	0.0		0.0
Long-term intercompany debt			0.0
Other non-current assets	(2,066.2)		(1,889.4)
Total other assets	(19,248.3)		(19,360.2)
Total assets	(19,257.8)		(19,390.7)
Current liabilities
Current maturities of long-term debt and short-term borrowings	0.0
Accounts payable	0.0		0.0
Employee compensation and benefits	0.0		0.0
Other current liabilities	(9.5)		(30.5)
Total current liabilities	(9.5)		(30.5)
Other liabilities
Long-term debt	(2,066.2)		(1,889.4)
Pension and other post-retirement compensation and benefits	0.0		0.0
Deferred tax liabilities	0.0		0.0
Other non-current liabilities	0.0		0.0
Total liabilities	(2,075.7)		(1,919.9)
Equity
Total equity	(17,182.1)		(17,470.8)
Total liabilities and equity	$ (19,257.8)		$ (19,390.7)