Accounting for and Classification of Discontinued Operations (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Aug. 31, 2011
Discontinued operations (net of tax) [Abstract]
Sales of real estate assets	$ 4.3	$ 0.4	$ 13.8	$ 19.5
Real estate leasing operations	0.1	1.0	0.8	3.2
CLX2 operating and shutdown losses	(14.0)	(1.3)	(33.1)	(1.3)
Total	(9.6)	0.1	(18.5)	21.4
Additional costs incurred, net of tax, not classified as discontinued operations			3.7
CLX2 Service [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of vessels used in discontinued operation					5
Number of vessels expected to be sub-chartered	2		2
Number of vessels returned to lessors	3		3
Duration of charter contracts (in years)	1Y		1Y
Fair value of obligations arising from exit activities	7.2		7.2
Revenue included in discontinued operations	$ 22.0	$ 5.7	$ 92.6	$ 5.7

After tax income (loss) from leasing operations of a business component (exclusive of any gain (loss) on disposal, or provision therefore) during the reporting period, until its disposal.

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After tax income(loss) from sales of assets of a business component on disposal, or provision therefore during the reporting period, until its disposal.

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The duration (in years) of the charter contracts for vessels used in the discontinued operation.

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The number of vessels used in the discontinued operation expected to be sub-chartered until returned to lessors in July 2012.

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The number of vessels used in the discontinued operation returned to the lessors pursuant to the terms of the one-year charter contracts for these vessels.

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The number of vessels used in the discontinued operation, for which the Company had established and approved plans to return to lessors or sub-charter.

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The charge against earnings in the period, comprised of costs incurred associated with an exit or disposal activity other than for a discontinued operations as defined under generally accepted accounting principles. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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After tax income (loss) from operations of a business component (exclusive of any gain (loss) on disposal, or provision therefore) during the reporting period, until its disposal.

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Amount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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This element represents the overall income (loss) from a disposal group apportioned to the parent that is classified as a component of the entity, net of income tax, reported as a separate component of income before extraordinary items after deduction or consideration of the amount which may be allocable to noncontrolling interests, if any. Includes the following (net of tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The obligations arising from the sale, disposal, or planned sale in the near future (generally within one year) of a disposal group, including a component of the entity (discontinued operation).

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