Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	9 Months Ended	1 Months Ended
Sep. 30, 2013 Practice_Groups	Aug. 30, 2013 Medical Management Professionals Business [Member]	Jul. 26, 2013 Medical Management Professionals Business [Member]
Summary Of Significant Accounting Policies [Line Items]
Aggregate Purchase price consideration paid during transaction			$ 201.6
Proceeds after payment of Divestiture Of Operation			$ 145.4
Number of Shares purchased from Westbury		3.85
Percentage of Holding		50.00%
Common stock, Per share Amount		$ 6.65
Number of practice groups	3

Disposal group business transferred amount under contractual arrangement.

No definition available.

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- Definition

Number of practice groups.

+ References

No definition available.

+ Details

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- Details

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

+ Details

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

+ References

No definition available.

+ Details

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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