General (Details 2) (USD $)	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Net revenues
Managed Care Revenue	$ 629,700,000	$ 601,800,000
Fee-For-Service and Cost-Plus Contracts Revenue	49,300,000	36,000,000
Block Grant Revenues	33,200,000	28,900,000
Performance-Based Revenue	1,900,000	8,000,000
Rebate revenues	8,700,000	9,700,000
Dispensing Revenue	94,121,000	87,154,000
Significant customers
Revenues generated	821,761,000	773,213,000
Maricopa County Regional Behavioral Health Authority
Significant customers
Number of members receiving behavioral healthcare management and other related services	680,000
Termination notice	10 days
Revenues generated	182,300,000	193,100,000
Magellan Complete Care of Arizona, Inc.
Significant customers
Percentage of investment in joint venture	80.00%
Vanguard/Phoenix Health Plan \| Magellan Complete Care of Arizona, Inc.
Significant customers
Percentage of investment in joint venture	20.00%
Commercial \| Customer A \| Service
Significant customers
Revenues generated	51,641,000	49,743,000
Commercial \| Customer B \| Service
Significant customers
Revenues generated	35,811,000	33,727,000
Commercial \| Customer C \| Service
Significant customers
Revenues generated	16,782,000	29,326,000
Minimum number of contracts per customer	1
Revenues related to terminated contract		13,200,000
Public Sector \| Customer D \| Service
Significant customers
Revenues generated	64,312,000	55,236,000
Number of contract extensions available under option	2
Contract extension period available under option	1 year
Radiology Benefits Management \| Customer E \| Service
Significant customers
Revenues generated	31,361,000	26,556,000
Radiology Benefits Management \| Customer F \| Service
Significant customers
Revenues generated	15,235,000	14,378,000
Radiology Benefits Management \| Customer G \| Service
Significant customers
Revenues generated	16,083,000	12,253,000
Radiology Benefits Management \| Customer H \| Service
Significant customers
Revenues generated	9,759,000	9,104,000
Pharmacy Solutions
Net revenues
Dispensing Revenue	94,121,000	87,154,000
Pharmacy Solutions \| Customer I \| Service
Significant customers
Revenues generated	33,311,000	31,044,000
Minimum number of contracts per customer	1
Pharmacy Solutions \| Customer J \| Service
Significant customers
Revenues generated	15,297,000	15,626,000
Minimum number of contracts per customer	1
Pharmacy Solutions \| Customer K \| Service
Significant customers
Revenues generated	21,641,000	14,647,000
Minimum number of contracts per customer	1
Pharmacy Solutions \| Customer L \| Service
Significant customers
Revenues generated	$ 15,245,000	$ 21,108,000

The number of additional periods (in years) available under contract extension options.

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The number of additional terms available under contract extension options.

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- Definition

Represents the revenue recognized, which includes the co-payments received from members of the health plans the company serves, when the specialty pharmaceutical drugs were shipped.

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No definition available.

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Represents the percentage of ownership held by the entity in the joint venture.

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Represents the minimum number of contracts entered by the entity per customer.

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Represents the number of members receiving behavioral healthcare management and other related services.

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Represents the revenue earned by the entity which is based upon the volume of rebates generated for its clients.

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Represents the revenues related to the contract that was terminated during the period.

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The number of days required for a customer to have the right to terminate a contract for cause.

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Revenue earned during the period arising from products sold or services provided under the terms of a contract, not elsewhere specified in the taxonomy. May include government contracts, construction contracts, and any other contract related to a particular project or product.

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Amount of revenue recognized that is not otherwise disclosed.

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Amount of revenues recognized from services provided to residents in facilities owned or operated by the health care organization (not including patient service revenue), which may be based on contractual rates set forth in agreements with third-party payers.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(d))

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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-Name Accounting Standards Codification

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-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=9156363&loc=d3e8184-115640

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-Name Audit and Accounting Guide (AAG)

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-Paragraph 10

-IssueDate 2006-05-01

-Chapter 8

-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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Revenue earned during the period from non-repayable sum of money awarded to an entity to carry out a specific purpose as provided in grant agreements.

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Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

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