Accrual of payment of working capital adjustment to sellers.

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Amount in which consideration paid exceeded the estimated fair value of the net tangible assets acquired.

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Number of states in which Arcadian Management Services and MD Care serve Medicare Advantage HMO members

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Total consideration paid including final working capital determination.

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Amount of cash paid to acquire the entity.

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Month, day and year when the business acquisition agreement was executed.

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The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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The calculated weighted-average useful life of all finite-lived intangible assets.

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Acquisitions (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	3 Months Ended		6 Months Ended		3 Months Ended
	Sep. 30, 2011	Sep. 30, 2011 Concentra Inc. Acquisition [Member]	Dec. 31, 2010 Concentra Inc. Acquisition [Member]	Jun. 30, 2011 Concentra Inc. Acquisition [Member]	Dec. 21, 2010 Concentra Inc. Acquisition [Member]	Sep. 30, 2011 Arcadian Management Services, Inc. And MD Care, Inc. [Member]
Date of acquisition		December 21, 2010
Cash consideration					$ 804.7
Accrual of payment of working capital adjustment to sellers				3.7
Total consideration paid including final working capital determination		808.4
Excess of consideration over estimated fair value of net tangible assets acquired		724.5
Amount allocated to other intangible assets		188.0
Goodwill acquired		536.5
Other intangible assets useful life	12.2	13.7
Acquired goodwill deductible for tax purposes		57.9
Acquisition-related costs			$ 14.9
Number of Medicare Advantage HMOs states served						15