Fair Value Measurements (Changes in Level 3 Assets and Liabilities Nonrecurring) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Changes in Level 3 Financial Assets and Liabilities, Non-Recurring Basis [Abstract]
Goodwill allocated to business sold	$ (40.0)
Nonrecurring [Member]
Changes in Level 3 Financial Assets and Liabilities, Non-Recurring Basis [Abstract]
Beginning balance: goodwill allocated to Medicare PDP business sold	0
Goodwill, Allocation Adjustment	40.0
Goodwill allocated to business sold	(40.0)
Ending balance: goodwill allocated to Medicare PDP business sold	0
Beginning balance: Deferred revenue	0
Additions	12.0
Deferred revenue, realized in net income	(12.0)
Ending balance: Deferred revenue	0
Lease impairment obligation, beginning balance	0
Liabilities, Fair Value Adjustment	7.4
Lease impairment obligation, ending balance	$ 7.4

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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a).Q1 Response)

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Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a).Q1)

-URI http://asc.fasb.org/extlink&oid=27012821&loc=d3e214044-122780

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

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Amount of previously reported deferred or unearned revenue that was recognized as revenue during the period. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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For the disposal group, including a component of the entity (discontinued operation), carrying amount of goodwill (adjusted for any amortization recognized prior to adoption of FAS 142 and impairment charges).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

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Fair value portion of other liabilities.

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