Other Operating Costs (Benefits) (Components of Other Operating Costs (Benefit)) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2010
Other Operating Costs (Benefit)
Adjustments to office closures obligations, discounted and net of expected sublease income	$ 580	$ (900)
Intangible assets impairment		7,307
Contingent acquisition liability adjustment	1,065
Other operating costs	$ 1,645	$ 6,407

Adjustments to Office Closure Obligations, Discounted And Net of Expected Sublease Income

No definition available.

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Section 50

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 46

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

Adjustment to the amount at which a liability incurred or settled in a current transaction between willing parties, that is, other than in a forced or liquidation sale.

+ References

No definition available.

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- Definition

The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation.

+ References

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 210.5-03.3)

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

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-Publisher SEC

-Name Regulation S-X (SX)

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-Section 03

-Paragraph 3

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