Guarantor and Non-Guarantor Financial Statements (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended				12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2013 Parent	Dec. 31, 2012 Parent	Dec. 31, 2011 Parent	Dec. 31, 2013 Guarantor Subsidiaries	Dec. 31, 2012 Guarantor Subsidiaries	Dec. 31, 2011 Guarantor Subsidiaries	Dec. 31, 2013 Non-Guarantor Subsidiaries	Dec. 31, 2012 Non-Guarantor Subsidiaries	Dec. 31, 2011 Non-Guarantor Subsidiaries	Dec. 31, 2013 Consolidating Adjustments	Dec. 31, 2012 Consolidating Adjustments	Dec. 31, 2011 Consolidating Adjustments	May 23, 2012 Senior Notes
Condensed Financial Statements [Line Items]
Principal amount of notes	$ 225.0				$ 225.0				$ 225.0	$ 225.0															$ 225.0
Ownership interest by parent	100.00%								100.00%
Current assets:
Cash and cash equivalents	169.5				273.4				169.5	273.4	49.8		5.0	5.0	5.0	157.7	266.0	43.0	6.8	2.4	1.8	0	0	0
Short-term investments	129.5				85.0				129.5	85.0			0	0		129.5	85.0		0	0		0	0
Receivables:
Trade, less allowance for doubtful receivables	119.8				123.8				119.8	123.8			0	0		117.7	121.5		2.1	2.3		0	0
Intercompany receivables	0				0				0	0			0	0		0.1	(10.3)		0.2	0.4		(0.3)	9.9
Other	13.4				3.4				13.4	3.4			0	0		5.3	1.3		8.1	2.1		0	0
Inventories	214.4				186.0				214.4	186.0			0	0		208.6	178.7		6.4	7.3		(0.6)	0
Prepaid expenses and other current assets	44.2				70.1				44.2	70.1			0.1	0		43.7	68.1		0.4	2.0		0	0
Total current assets	690.8				741.7				690.8	741.7			5.1	5.0		662.6	710.3		24.0	16.5		(0.9)	9.9
Investments in and advances to unconsolidated affiliates	0				0				0	0			1,437.9	1,284.1		26.5	7.4		0	0		(1,464.4)	(1,291.5)
Property, plant, and equipment — net	429.3				384.3				429.3	384.3			0	0		414.0	371.8		15.3	12.5		0	0
Long-term intercompany receivables	0				0				0	0			31.3	163.7		1.6	0.4		9.5	6.4		(42.4)	(170.5)
Net asset in respect of VEBAs	406.0				365.9				406.0	365.9			0	0		406.0	365.9		0	0		0	0
Deferred tax assets — net	69.1				102.0				69.1	102.0			0	0		60.2	93.4		0	(0.8)		8.9	9.4
Intangible assets — net	33.7				35.4				33.7	35.4			0	0		33.7	35.4		0	0		0	0
Goodwill	37.2				37.2				37.2	37.2			0	0		37.2	37.2		0	0		0	0
Other assets	104.8				86.0				104.8	86.0			86.2	64.0		18.5	19.2		0.1	3.0		0	(0.2)
Total	1,770.9				1,752.5				1,770.9	1,752.5	1,320.6		1,560.5	1,516.8		1,660.3	1,641.0		48.9	37.6		(1,498.8)	(1,442.9)
Current liabilities:
Accounts payable	62.9				62.5				62.9	62.5			1.1	0.1		56.3	56.5		5.5	5.9		0	0
Intercompany payable	0				0				0	0			0	0		13.9	0.3		0.1	0.2		(14.0)	(0.5)
Accrued salaries, wages, and related expenses	42.7				39.3				42.7	39.3			0	0		39.3	36.7		3.4	2.6		0	0
Other accrued liabilities	44.8				51.8				44.8	51.8			3.5	3.5		39.9	47.8		1.4	0.5		0	0
Payable to affiliate	0				7.9				0	7.9				0			7.9			0			0
Short-term capital leases	0.2				0.1				0.2	0.1			0	0		0.2	0.1		0	0		0	0
Total current liabilities	150.6				161.6				150.6	161.6			4.6	3.6		149.6	149.3		10.4	9.2		(14.0)	(0.5)
Net liability in respect of VEBA	0				5.3				0	5.3				0			5.3			0			0
Deferred tax liability	1.2				0				1.2	0			0			0			1.2			0
Long-term intercompany payable	0				0				0	0			0	0		40.7	170.0		1.7	0.5		(42.4)	(170.5)
Long-term liabilities	146.4				134.5				146.4	134.5			83.2	62.1		52.0	49.6		11.2	22.8		0	0
Long-term debt	388.5				380.3				388.5	380.3			388.5	380.3		0	0		0	0		0	0
Total liabilities	686.7				681.7				686.7	681.7			476.3	446.0		242.3	374.2		24.5	32.5		(56.4)	(171.0)
Total stockholders’ equity	1,084.2				1,070.8				1,084.2	1,070.8	872.8	888.7	1,084.2	1,070.8		1,418.0	1,266.8		24.4	5.1		(1,442.4)	(1,271.9)
Total	1,770.9				1,752.5				1,770.9	1,752.5			1,560.5	1,516.8		1,660.3	1,641.0		48.9	37.6		(1,498.8)	(1,442.9)
CONDENSED CONSOLIDATING STATEMENT OF COMPREHENSIVE INCOME
Net sales	311.3	319.9	328.9	337.4	314.0	335.5	345.2	365.4	1,297.5	1,360.1	1,301.3		0	0	0	1,275.2	1,326.0	1,264.5	118.0	124.0	133.6	(95.7)	(89.9)	(96.8)
Cost of products sold:
Cost of products sold, excluding depreciation and amortization and other items	254.3	259.5	261.5	263.6	264.8	268.9	284.4	298.1	1,038.9	1,116.2	1,129.0		0	0	0	1,026.0	1,090.0	1,098.7	105.7	110.2	125.4	(92.8)	(84.0)	(95.1)
Unrealized (gains) losses on derivative instruments	(4.1)	(1.5)	4.2	0.7	0.1	(12.3)	0.1	(3.1)	(0.7)	(15.2)	29.9		0	0	0	(0.7)	(15.2)	29.9	0	0	0	0	0	0
Restructuring benefits									0	0	(0.3)				0			(0.3)			0			0
Depreciation and amortization									28.1	26.5	25.2		0	0	0	27.0	25.5	24.3	1.1	1.0	0.9	0	0	0
Selling, administrative, research and development, and general (includes accumulated other comprehensive income reclassifications related to VEBA and Canadian pension plan adjustments of $5.7, $7.3 and $4.8 for the years ended 2013, 2012 and 2011, respectively) - See Note 7									57.9	62.2	62.7		3.8	2.0	1.8	47.6	57.7	56.3	8.9	8.2	6.2	(2.4)	(5.7)	(1.6)
Other operating (benefits) charges, net										4.5	(0.2)			0	0		4.5	0.1		0	(0.3)		0	0
Total costs and expenses									1,124.2	1,194.2	1,246.3		3.8	2.0	1.8	1,099.9	1,162.5	1,209.0	115.7	119.4	132.2	(95.2)	(89.7)	(96.7)
Operating (loss) income	41.6	41.6	40.1	50.0	23.9	56.2	39.6	46.2	173.3	165.9	55.0		(3.8)	(2.0)	(1.8)	175.3	163.5	55.5	2.3	4.6	1.4	(0.5)	(0.2)	(0.1)
Interest expense									(35.7)	(29.1)	(18.0)		(36.6)	(28.2)	(16.2)	0.5	(1.0)	(1.8)	0	0	0	0.4	0.1	0
Other (expense) income:
Other income, net									5.6	2.8	4.3		3.9	0.8	4.0	2.0	1.5	0.4	0	0.6	(0.1)	(0.3)	(0.1)	0
(Loss) income before income taxes									143.2	139.6	41.3		(36.5)	(29.4)	(14.0)	177.8	164.0	54.1	2.3	5.2	1.3	(0.4)	(0.2)	(0.1)
Income tax provision									(38.4)	(53.8)	(16.2)		0	0	0	(68.1)	(62.6)	(21.8)	15.7	(2.3)	(0.6)	14.0	11.1	6.2
Earnings in equity of subsidiaries									0	0	0		141.3	115.2	39.1	17.6	2.6	0.8	0	0	0	(158.9)	(117.8)	(39.9)
Net income	27.3	25.4	18.6	33.5	9.1	29.2	21.0	26.5	104.8	85.8	25.1		104.8	85.8	25.1	127.3	104.0	33.1	18.0	2.9	0.7	(145.3)	(106.9)	(33.8)
Comprehensive income (loss)									110.1	144.8	(40.2)		110.1	144.8	(40.2)	131.6	164.0	(32.2)	19.0	1.9	0.7	(150.6)	(165.9)	31.5
Cash flows from operating activities:
Net cash (used in) provided by operating activities									111.7	152.4	62.8		(29.2)	(17.8)	(10.2)	131.7	164.3	71.9	9.2	5.9	1.1	0	0	0
Cash flows from investing activities:
Capital expenditures									(70.4)	(44.1)	(32.5)		0	0	0	(66.5)	(42.6)	(31.2)	(3.9)	(1.5)	(1.3)	0	0	0
Purchase of available for sale securities									(227.8)	(85.0)	(0.3)		0	0	0	(227.8)	(85.0)	(0.3)		0	0	0	0	0
Proceeds from disposition of available for sale securities									183.1	0	0		0			183.1			0			0
Proceeds from disposal of property, plant and equipment									0	0.3	0.7			0	0		0.3	0		0	0.7		0	0
Cash payment for acquisition of manufacturing facility and related assets (net of $4.9 of cash received in connection with the acquisition in 2011)									0	0	(83.2)				0			(83.2)			0			0
Change in restricted cash									1.7	6.9	(1.0)		0	6.9	0	0.7	0.4	(1.0)	1.0	(0.4)	0	0	0	0
Net cash provided by (used in) investing activities									(113.4)	(121.9)	(116.3)		0	6.9	0	(110.5)	(126.9)	(115.7)	(2.9)	(1.9)	(0.6)	0	0	0
Cash flows from financing activities:
Proceeds from issuance of Senior Notes									0	225.0	0			225.0			0			0			0
Repayments of capital lease									(0.1)	(0.1)	(0.1)		0	0	0	(0.1)	(0.1)	(0.1)	0	0	0	0	0	0
Repayment of promissory notes									0	(4.7)	(8.3)			0	0		(4.7)	(8.3)		0	0		0	0
Cash paid for financing costs									0	(6.6)	(2.1)			(6.6)	0		0	(2.1)		0	0		0	0
Repurchase of common stock									(78.3)	0	0		(78.3)			0			0			0
Excess tax benefit upon vesting of non-vested shares and dividend payment on unvested shares expected to vest									1.1	1.3	0.2		0	0	0	1.1	1.3	0.2	0	0	0	0	0	0
Repurchase of common stock to cover employees' tax withholdings upon vesting of non-vested shares									(2.5)	(2.2)	(3.1)		(2.5)	(2.2)	(3.1)	0	0	0	0	0	0	0	0	0
Cash dividend paid to stockholders									(23.0)	(19.6)	(18.9)		(23.0)	(19.6)	(18.9)	0	0	0	0	0	0	0	0	0
Cash dividend returned to the Company			0.6						0.6	0	0		0.6			0			0			0
Intercompany loan									0	0	0		132.4	(185.7)	32.2	(130.5)	189.1	(32.5)	(1.9)	(3.4)	0.3	0	0	0
Net cash provided by (used in) financing activities									(102.2)	193.1	(32.3)		29.2	10.9	10.2	(129.5)	185.6	(42.8)	(1.9)	(3.4)	0.3	0	0	0
Net (decrease) increase in cash and cash equivalents during the period									(103.9)	223.6	(85.8)		0	0	0	(108.3)	223.0	(86.6)	4.4	0.6	0.8	0	0	0
Cash and cash equivalents at beginning of period				273.4				49.8	273.4	49.8	135.6		5.0	5.0	5.0	266.0	43.0	129.6	2.4	1.8	1.0	0	0	0
Cash and cash equivalents at end of period	$ 169.5				$ 273.4				$ 169.5	$ 273.4	$ 49.8		$ 5.0	$ 5.0	$ 5.0	$ 157.7	$ 266.0	$ 43.0	$ 6.8	$ 2.4	$ 1.8	$ 0	$ 0	$ 0