Income Taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Components of Deferred Tax Assets and Liabilities [Abstract]
Net operating loss carryforwards	$ 410,800,000	$ 453,900,000
Pension and postretirement benefits	144,600,000	155,000,000
Other	69,900,000	70,800,000
Total deferred tax assets	625,300,000	679,700,000
Valuation allowance	(56,800,000)	(58,400,000)
Net deferred tax assets, net of valuation allowance	568,500,000	621,300,000
Property, plant and equipment	125,100,000	159,800,000
Federal deferred liability on state deferred tax assets	7,200,000	7,800,000
Deferred Tax Liabilities, Other	1,600,000	0
Total deferred tax liabilities	133,900,000	167,600,000
Net deferred tax assets	434,600,000	453,700,000
Deferred Tax Assets, Operating Loss Carryforwards, Components [Abstract]
Operating Loss Carryforwards	1,000,000,000
Operating Loss Carryforwards, Valuation Allowance	352,000,000
Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax	16,500,000
Deferred Tax Assets, Tax Credit Carryforwards	11,400,000
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	58,800,000
Operating Loss Carryforwards, Expiration Dates	between 2021 and 2023
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	22,300,000	21,500,000
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
U.S. federal statutory rate	35.00%	35.00%	35.00%
State and local income taxes, net of federal income tax	3.90%	2.90%	2.60%
Change in valuation allowance, net of federal income tax	(2.30%)	(4.40%)	(7.10%)
State net operating loss adjustments	3.70%	2.70%	0.10%
Nondeductible interest expense	18.10%	15.00%	13.30%
Medicare drug subsidy law change	0.00%	0.00%	5.80%
Unrecognized tax benefit changes	2.20%	2.80%	5.70%
Nondeductible compensation	2.70%	2.10%	1.50%
Foreign	3.50%	0.10%	0.80%
Other differences, net	2.00%	1.10%	0.20%
Effective tax rate	68.80%	57.30%	57.90%
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Federal, current	1,800,000	0	300,000
State and local, current	1,600,000	400,000	700,000
Total current	3,400,000	400,000	1,000,000
Investment tax credits	(300,000)	(300,000)	(300,000)
Federal, deferred	21,800,000	24,300,000	44,000,000
State and local, deferred	2,000,000	3,400,000	1,400,000
Deferred Foreign Income Tax Expense (Benefit)	(500,000)	100,000	0
Total deferred	23,300,000	27,800,000	45,400,000
Valuation allowance	(1,700,000)	(2,900,000)	(7,200,000)
Total	24,700,000	25,000,000	38,900,000
Other Comprehensive Income (Loss), Tax	(400,000)	(26,500,000)	(13,200,000)
Employee Service Share-based Compensation, Tax Benefit Realized from Exercise of Stock Options	(2,400,000)	0	0
Income Tax Uncertainties [Abstract]
Balance, beginnging of year	21,800,000	20,500,000	16,700,000
Change in tax positions for the current year	1,400,000	1,300,000	4,000,000
Change in tax positions for prior years	(400,000)	0	(200,000)
Balance, end of year	$ 22,800,000	$ 21,800,000	$ 20,500,000