Share-based Compensation Plans (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost	$ 6.6	$ 8.6	$ 12.1
Income tax benefit from compensation cost	2.3	3.0	4.2
Shares subject to option [Roll Forward]
Granted (in shares)	0	0	0
Exercised (in shares)	0	0	0
Shares [Roll Forward]
Restricted stock outstanding at end of period (in shares)	3,600,000
Stock Options [Member]
Shares subject to option [Roll Forward]
Options exercisable (in shares)	529,800
Options exercisable, weighted average exercise price (in dollars per share)	$ 68.20
Restricted Stock/Restricted Stock Units [Member]
Weighted average grant date fair market value [Abstract]
Restricted stock outstanding at end of period (in dollars per share)	$ 7.08
Granted (in dollars per share)	$ 2.75	$ 3.97	$ 8.94
Vested (in dollars per share)	$ 6.36
Forfeited (in dollars per share)	$ 3.37
Restricted stock outstanding at end of period (in dollars per share)	$ 5.15	$ 7.08
Shares [Roll Forward]
Restricted stock outstanding at beginning of period (in shares)	3,077,582
Granted (in shares)	1,853,800
Vested (in shares)	(1,273,215)
Forfeited (in shares)	(35,460)
Restricted stock outstanding at end of period (in shares)	3,622,707	3,077,582
Additional disclosures [Abstract]
Restricted stock, performance shares (in shares)	2,700,000
Restricted stock, time vested shares (in shares)	900,000
Total fair value of restricted stock vested	4.3	6.9	14.9
Unrecognized compensation cost	8.3
Unrecognized compensation cost, performance shares	6.9
Unrecognized compensation cost, time vested shares	1.4
Weighted-average period for recognition of compensation cost	1 year 7 months 6 days
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
2002 Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Cash Settled Award [Member]
Weighted average grant date fair market value [Abstract]
Granted (in dollars per share)			$ 8.94
Shares [Roll Forward]
Restricted stock outstanding at beginning of period (in shares)	294,782	443,950	0
Granted (in shares)	0	0	449,350
Vested (in shares)	(147,368)	(147,968)	0
Forfeited (in shares)	(3,268)	(1,200)	(5,400)
Restricted stock outstanding at end of period (in shares)	144,146	294,782	443,950
Cash payments for vested shares	0.4	0.6
Additional disclosures [Abstract]
Unrecognized compensation cost	$ 0.1
Weighted-average period for recognition of compensation cost	0 years 1 month 6 days
2011 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares can be awarded under the plan (in shares)	7,000,000
Additional disclosures [Abstract]
Shares available for future grants (in shares)	3,600,000

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The amount of cash payments for vested shares during the reporting period for the cash settled restricted stock units.

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The portion of the restricted shares outstanding as of the balance sheet date that consisted of shares that are subject to performance conditions.

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The portion of the restricted shares outstanding as of the balance sheet date that consisted of shares that are subject only to service conditions.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based performance share awards made to employees under equity-based compensation awards that have yet to vest.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based time vested share awards made to employees under equity-based compensation awards that have yet to vest.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Net number of share options (or share units) granted during the period.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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Number of share options (or share units) exercised during the current period.

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