Supplemental Balance Sheet Information (Tables)

12 Months Ended

Dec. 31, 2013

Supplemental Balance Sheet Information [Abstract]

Cash and Cash Equivalents

	December 31, 2013		December 31, 2012
Cash and Cash Equivalents.
Cash and money market funds	$	57.7	$	107.9
Commercial paper	111.8		165.5
Total	$	169.5	$	273.4

Trade Receivables

Trade Receivables.
Billed trade receivables	$	120.2		$	124.4
Unbilled trade receivables — Note 1	0.4			0.2
Trade receivables, gross	120.6			124.6
Allowance for doubtful receivables	(0.8		)	(0.8		)
Trade receivables, net	$	119.8		$	123.8

Inventories

Inventories.
Finished products	$	72.5	$	59.9
Work-in-process	75.9		55.5
Raw materials	47.2		53.9
Operating supplies and repairs and maintenance parts	18.8		16.7
Total	$	214.4	$	186.0

Prepaid Expenses and Other Current Assets

Prepaid Expenses and Other Current Assets.
Current derivative assets — Notes 11 and 12	$	2.0	$	3.0
Current deferred tax assets	36.7		59.5
Current portion of option premiums paid — Notes 11 and 12	—		0.1
Short-term restricted cash	0.3		1.3
Prepaid taxes	—		2.1
Prepaid expenses	5.2		4.1
Total	$	44.2	$	70.1

Property, Plant and Equipment - Net

Property, Plant, and Equipment - Net.
Land and improvements	$	22.6		$	22.6
Buildings and leasehold improvements	53.0			50.9
Machinery and equipment	425.6			400.4
Construction in progress	66.0			20.8
Active property, plant, and equipment, gross	567.2			494.7
Accumulated depreciation	(137.9		)	(111.4		)
Active property, plant, and equipment, net	429.3			383.3
Idled equipment	—			1.0
Property, plant, and equipment, net	$	429.3		$	384.3

Other Assets

Other Assets.
Derivative assets — Notes 11 and 12	$	79.8	$	55.5
Restricted cash	9.3		10.0
Long-term income tax receivable	—		2.9
Deferred financing costs	8.9		11.7
Deferred compensation plan assets	6.5		5.6
Other	0.3		0.3
Total	$	104.8	$	86.0

Other Accrued Liabilities

Other Accrued Liabilities.
Current derivative liabilities — Notes 11 and 12	$	1.8	$	3.1
Current portion of option premiums received — Notes 11 and 12	—		0.1
Uncleared cash disbursement	9.6		4.7
Accrued income taxes and taxes payable	4.3		3.1
Accrued annual VEBA contribution	16.0		20.0
Short-term environmental accrual — Note 10	2.8		3.0
Accrued interest	3.7		3.7
Short-term deferred revenue — Note 1	—		6.7
Other	6.6		7.4
Total	$	44.8	$	51.8

Long-term Liabilities

Long-term Liabilities.
Derivative liabilities — Notes 11 and 12	$	84.3	$	63.5
Income tax liabilities	5.0		15.1
Workers’ compensation accruals	23.3		24.0
Long-term environmental accrual — Note 10	20.0		18.7
Long-term asset retirement obligations	4.0		3.8
Deferred compensation liability	7.0		5.8
Long-term capital leases	0.1		0.2
Other long-term liabilities	2.7		3.4
Total	$	146.4	$	134.5

Long-term Debt

Long-term Debt. — Note 3
Senior notes	$	225.0	$	225.0
Cash convertible senior notes	163.5		155.3
Total	$	388.5	$	380.3