Business Combinations (Details Textual) (USD $)	9 Months Ended
Sep. 30, 2012	Dec. 31, 2011
Business Combinations (Additional Textual) [Abstract]
Aggregate purchase price		$ 101,900,000
Excess of the purchase price over the estimated fair value of the net tangible assets	89,600,000
Preliminarily allocated approximately to goodwill		74,391,000
Preliminarily allocated approximately to other intangible assets		15,200,000
Customer-related intangible		14,726,000
Marketing-related intangibles		$ 484,000
Customer Related [Member]
Business Combinations (Textual) [Abstract]
Amortized, acquisition date	7 years
Market Related [Member]
Business Combinations (Textual) [Abstract]
Amortized, acquisition date	1 year
Symbiotic Engineering L.L.C [Member]
Business Combinations (Textual) [Abstract]
Business acquisition, date of acquisition	Sep. 01, 2012
AeroStrategy L.L.C. [Member]
Business Combinations (Textual) [Abstract]
Business acquisition, date of acquisition	Sep. 01, 2011
Marbek Resource Consultants Ltd. [Member]
Business Combinations (Textual) [Abstract]
Business acquisition, date of acquisition	Jan. 01, 2011
Ironworks Consulting, L.L.C. [Member]
Business Combinations (Textual) [Abstract]
Business acquisition, date of acquisition	Dec. 31, 2011
Amortization of Intangibles deductible period	15 years
GHK Holdings Limited [Member]
Business Combinations (Textual) [Abstract]
Business acquisition, date of acquisition	Feb. 01, 2012

Amortization of Intangibles deductible period.

No definition available.

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- Definition

The amount of acquisition cost of a business combination allocated to a customer-related intangible asset.

+ References

No definition available.

+ Details

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- Definition

The amount of acquisition cost of a business combination allocated to a marketing-related intangible asset.

+ References

No definition available.

+ Details

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- Definition

The aggregate amount assigned to a major class of finite-lived intangible assets acquired either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 44

-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 total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-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.

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- Definition

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

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-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 6

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Acquisition Date

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-Publisher FASB

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-Topic 805

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-Section 25

-Paragraph 7

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- Definition

Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 52

-Subparagraph c

-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 Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 53

-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.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- 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

Reference 1: 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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

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

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph e

-Clause 2

-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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