Statement of Consolidated Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash flows from operating activities:
Net income	$ 104.8	$ 85.8	$ 25.1
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation of property, plant and equipment	26.4	24.7	23.0
Amortization of definite-lived intangible assets	1.7	1.8	2.2
Amortization of debt discount and debt issuance costs	11.0	9.8	8.6
Deferred income taxes	55.4	52.0	17.6
Excess tax benefit upon vesting of non-vested shares and dividend payment on unvested shares expected to vest	(1.1)	(1.3)	(0.2)
Non-cash equity compensation	6.8	5.8	5.4
Net non-cash LIFO benefits	(24.1)	(4.9)	(7.1)
Non-cash unrealized (gains) losses on derivative instruments	(3.9)	(16.0)	25.9
Amortization of option premiums (received) paid, net	(0.1)	0.3	(1.2)
Non-cash impairment charges	0	4.4	0
Losses (gains) on disposition of property, plant and equipment	0.1	(0.1)	0.2
Gain on disposition of available for sale securities	(0.4)	0	0
Non-cash defined benefit net periodic benefit income	(22.0)	(11.5)	(5.7)
Other non-cash changes in assets and liabilities	(9.3)	1.2	0.4
Changes in operating assets and liabilities, net of effect of acquisition:
Trade and other receivables	(3.3)	(27.1)	(8.3)
Inventories (excluding LIFO adjustments)	(4.3)	24.6	(24.5)
Prepaid expenses and other current assets	1.1	1.4	(2.9)
Accounts payable	(1.6)	(1.3)	10.9
Accrued liabilities (includes the effect of the VEBA contribution accrual of $16.0 at December 31, 2013 and $20.0 at December 31, 2012)	(18.2)	10.4	(1.5)
Payable to affiliate	(7.9)	(6.5)	(2.7)
Long-term assets and liabilities, net	0.6	(1.1)	(2.4)
Net cash provided by operating activities	111.7	152.4	62.8
Cash flows from investing activities:
Capital expenditures	(70.4)	(44.1)	(32.5)
Purchase of available for sale securities	(227.8)	(85.0)	(0.3)
Proceeds from disposition of available for sale securities	183.1	0	0
Proceeds from disposal of property, plant and equipment	0	0.3	0.7
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)
Change in restricted cash	1.7	6.9	(1.0)
Net cash used in investing activities	(113.4)	(121.9)	(116.3)
Cash flows from financing activities:
Proceeds from issuance of Senior Notes	0	225.0	0
Payment of capital lease liability	(0.1)	(0.1)	(0.1)
Repayment of promissory notes	0	(4.7)	(8.3)
Cash paid for financing costs	0	(6.6)	(2.1)
Excess tax benefit upon vesting of non-vested shares and dividend payment on unvested shares expected to vest	1.1	1.3	0.2
Repurchase of common stock to cover employees' tax withholdings upon vesting of non-vested shares	(2.5)	(2.2)	(3.1)
Repurchase of common stock	(78.3)	0	0
Cash dividend paid to stockholders	(23.0)	(19.6)	(18.9)
Cash dividend returned to the Company	0.6	0	0
Net cash (used in) provided by financing activities	(102.2)	193.1	(32.3)
Net (decrease) increase in cash and cash equivalents during the period	(103.9)	223.6	(85.8)
Cash and cash equivalents at beginning of period	273.4	49.8	135.6
Cash and cash equivalents at end of period	$ 169.5	$ 273.4	$ 49.8