Related Party Transactions	6 Months Ended
Related Party Transactions	Jun. 30, 2011
Related Party Transactions [Abstract]
Related Party Transactions	13. Related Party Transactions We have an equity investment in a medical service provider that provides certain vision services to our members. We account for this investment under the equity method of accounting because we have an ownership interest in the investee that confers significant influence over operating and financial policies of the investee. As of both June 30, 2011, and December 31, 2010, our carrying amount for this investment totaled $4.4 million. For the three months ended June 30, 2011 and 2010, we paid $6.6 million, and $5.3 million, respectively, for medical service fees to this provider. For the six months ended June 30, 2011 and 2010, we paid $11.9 million, and $9.7 million, respectively, for medical service fees to this provider.

The entire disclosure for related party transactions, including the nature of the relationship(s), a description of the transactions, the amount of the transactions, the effects of any change in the method of establishing the terms of the transaction from the previous period, stated interest rate, expiration date, terms and manner of settlement per the agreement with the related party, and amounts due to or from related parties. If the entity and one or more other entities are under common ownership or management control and this control affects the operating results or financial position, disclosure includes the nature of the control relationship even if there are no transactions between the entities. Disclosure may also include the aggregate amount of current and deferred tax expense for each statement of earnings presented where the entity is a member of a group that files a consolidated tax return, the amount of any tax related balances due to or from affiliates as of the date of each statement of financial position presented, the principal provisions of the method by which the consolidated amount of current and deferred tax expense is allocated to the members of the group and the nature and effect of any changes in that method. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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