Goodwill and Identifiable Assets (Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2011
Goodwill [Roll Forward]
Gross goodwill	$ 496,553		$ 617,875	$ 350,951
Accumulated impairment loss	0		(121,717)	(121,717)
Goodwill	496,553		496,158	229,234
Acquisition			264,590
Goodwill, Purchase Accounting Adjustments	0	(982)	1,805
Goodwill, Written off Related to Sale of Business Unit	(121,717)
Write-off of accum impairment loss related to sale of business unit	121,717
Translation adjustment	395		529
Apex
Goodwill [Roll Forward]
Gross goodwill	264,590		264,590	0
Accumulated impairment loss	0		0	0
Goodwill	264,590		264,590	0
Acquisition			264,590
Translation adjustment	0		0
Oxford
Goodwill [Roll Forward]
Gross goodwill	149,483		149,483	149,483
Accumulated impairment loss	0		0	0
Goodwill	149,483		149,483	149,483
Translation adjustment	0		0
Life Sciences
Goodwill [Roll Forward]
Gross goodwill	30,406		30,011	27,668
Accumulated impairment loss	0		0	0
Goodwill	30,406		30,011	27,668
Acquisition			0
Goodwill, Purchase Accounting Adjustments			1,814
Translation adjustment	395		529
Healthcare
Goodwill [Roll Forward]
Gross goodwill	513		122,230	122,230
Accumulated impairment loss	0		(121,717)	(121,717)
Goodwill	513		513	513
Goodwill, Written off Related to Sale of Business Unit	(121,717)
Write-off of accum impairment loss related to sale of business unit	121,717
Translation adjustment	0		0
Physician
Goodwill [Roll Forward]
Gross goodwill	51,561		51,561	51,570
Accumulated impairment loss	0		0	0
Goodwill	51,561		51,561	51,570
Translation adjustment	0		0
Physician \| Health Care Partners [Member]
Goodwill [Roll Forward]
Goodwill, Purchase Accounting Adjustments			$ (9)

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph l

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph e

-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 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 43

-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 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 72

-Subparagraph d

-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 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph e

-Clause 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.

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 34

-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.

+ Details

- Definition

The aggregate amount of goodwill acquired in the period and allocated to the reportable segment. The value is stated at fair value based on the purchase price allocation.

+ References+ Details

- Definition

Write-off of the carrying amount of goodwill associated with all or a portion of a reporting unit that is sold in the period.

+ References+ Details