Joint Ventures (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Joint Venture
Investment in equity	$ 1,225
MCCAZ
Joint Venture
Ownership percentage	80.00%
Investment in equity	1,500
Fallon Total Care
Joint Venture
Ownership percentage	49.00%
Investment in equity	$ 1,200
Number of particpants from reporting entity	2
Term of demonstration program	3 years
Number of counties across Massachusetts served under the demonstration program	10
Fallon Total Care \| Minimum
Joint Venture
Age of individuals to whom integrated healthcare will be provided under demonstration program	21
Fallon Total Care \| Maximum
Joint Venture
Age of individuals to whom integrated healthcare will be provided under demonstration program	64
Fallon Total Care \| Fallon Community Health Plan, Co-Venturer
Joint Venture
Ownership percentage	51.00%

Represents the age of individuals to whom healthcare service will be provided under the program.

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- Definition

Represents the number of countries served under the demonstration program.

+ References

No definition available.

+ Details

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- Definition

Represents the number of participants from the reporting entity.

+ References

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- Definition

Represents information pertaining to the term of demonstration program.

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a (1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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- Definition

The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

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-Publisher FASB

-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.

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