Summary of Significant Accounting Policies and Recently Issued Accounting Standards - Summary of Financial Statement (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended									12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013		Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Consolidated Statements of Operations:
Cost of sales										$ 5,062.9	$ 5,100.9	[1]	$ 5,038.7	[1]
Gross profit	672.3	696.1	679.6	639.6	668.6		650.4	656.6	614.3	2,687.6	2,589.9	[1]	2,520.5	[1]
Earnings (loss) from continuing operations before income tax provision (benefit)										267.2	180.2	[1]	(1,884.4)	[1]
Income tax provision (benefit)										9.1	84.9	[1]	(265.4)	[1]	16.0
Net earnings (loss) available to common stockholders from continuing operations	66.3	60.8	60.1	70.9	5.0		35.5	52.7	2.1	258.1	95.3	[1],[2]	(1,619.0)	[1],[2]
Net earnings (loss)	66.3	60.8	60.1	70.9	29.0		38.0	54.7	4.1	258.1	125.8	[1]	(1,411.4)	[1]
Net earnings (loss) per common share:
Continuing operations	$ 0.31	$ 0.29	$ 0.28	$ 0.34	$ 0.03		$ 0.18	$ 0.27	$ 0.01	$ 1.22	$ 0.49	[1]	$ (8.40)	[1]
Continuing operations	$ 0.31	$ 0.28	$ 0.28	$ 0.33	$ 0.02		$ 0.17	$ 0.24	$ 0.01	$ 1.20	$ 0.44	[1]	$ (8.40)	[1]
Consolidated Statements of Comprehensive Income:
Net earnings (loss)	66.3	60.8	60.1	70.9	29.0		38.0	54.7	4.1	258.1	125.8	[1]	(1,411.4)	[1]
Comprehensive income (loss), net of taxes										(78.3)	13.3	[1]	(1,431.2)	[1]
Consolidated Statements of Cash Flows:
Net cash (used in) provided by operating activities from continuing operations										(201.9)	624.8	[2]	394.2	[2]
Net earnings (loss) available to common stockholders from continuing operations	66.3	60.8	60.1	70.9	5.0		35.5	52.7	2.1	258.1	95.3	[1],[2]	(1,619.0)	[1],[2]
Inventories										(48.6)	22.0	[2]	35.2	[2]
Deferred taxes, net										136.1	7.9	[2]	(319.3)	[2]
Consolidated Balance Sheets:
Inventories	707.6				730.2	[2]				707.6	730.2	[2]
Non-current deferred taxes	161.5				294.6	[2]				161.5	294.6	[2]
Retained earnings	448.5				302.2	[2]				448.5	302.2	[2]	279.0
Effect of change Increase (Decrease)
Consolidated Statements of Operations:
Cost of sales										1.5	(2.4)		1.8
Gross profit										(1.5)	2.4		(1.8)
Earnings (loss) from continuing operations before income tax provision (benefit)										(1.5)	2.4		(1.8)
Income tax provision (benefit)										(0.6)	0.9		(0.7)
Net earnings (loss) available to common stockholders from continuing operations										(0.9)	1.6		(1.1)
Net earnings (loss)										(0.9)	1.6		(1.1)
Net earnings (loss) per common share:
Continuing operations											$ 0.01		$ (0.01)
Continuing operations													$ (0.01)
Consolidated Statements of Comprehensive Income:
Net earnings (loss)										(0.9)	1.6		(1.1)
Comprehensive income (loss), net of taxes										(0.9)	1.6		(1.1)
Consolidated Statements of Cash Flows:
Net earnings (loss) available to common stockholders from continuing operations										(0.9)	1.6		(1.1)
Inventories										1.5	(2.5)		1.8
Deferred taxes, net										(0.6)	0.9		(0.7)
Consolidated Balance Sheets:
Inventories	40.3				41.8					40.3	41.8
Non-current deferred taxes	15.4				16.0					15.4	16.0
Retained earnings	24.9				25.8					24.9	25.8		24.2
As computed under LIFO
Consolidated Statements of Operations:
Cost of sales										5,061.4	5,103.3		5,036.9
Gross profit										2,689.1	2,587.5		2,522.3
Earnings (loss) from continuing operations before income tax provision (benefit)										268.7	177.8		(1,882.6)
Income tax provision (benefit)										9.7	84.0		(264.7)
Net earnings (loss) available to common stockholders from continuing operations										259.0	93.7		(1,617.9)
Net earnings (loss)										259.0	124.2		(1,410.3)
Net earnings (loss) per common share:
Continuing operations										$ 1.22	$ 0.48		$ (8.39)
Continuing operations										$ 1.20	$ 0.44		$ (8.39)
Consolidated Statements of Comprehensive Income:
Net earnings (loss)										259.0	124.2		(1,410.3)
Comprehensive income (loss), net of taxes										(77.4)	11.7		(1,430.1)
Consolidated Statements of Cash Flows:
Net cash (used in) provided by operating activities from continuing operations										(201.9)	624.8		394.2
Net earnings (loss) available to common stockholders from continuing operations										259.0	93.7		(1,617.9)
Inventories										(50.1)	24.5		33.4
Deferred taxes, net										136.7	7.0		(318.6)
Consolidated Balance Sheets:
Inventories	667.3				688.4					667.3	688.4
Non-current deferred taxes	146.1				278.6					146.1	278.6
Retained earnings	$ 423.6				$ 276.4					$ 423.6	$ 276.4		$ 254.8

[1] Certain amounts have been revised to reflect the retrospective application of the Company’s change in inventory costing method for certain U.S. inventories to the FIFO method from the LIFO method. Refer to Note 2, “Summary of Significant Accounting Policies - Inventories,” of the notes to consolidated financial statements for further details surrounding this accounting policy change.

[2] Certain amounts have been revised to reflect the retrospective application of the Company’s change in inventory costing method for certain U.S. inventories to the FIFO method from the LIFO method. Refer to Note 2, “Summary of Significant Accounting Policies - Inventories,” of the notes to consolidated financial statements for further details surrounding this accounting policy change.