Business Combinations (Details Textual) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Business Combinations (Textual) [Abstract]
Preliminarily allocated approximately to goodwill		$ 74,379,000
Customer-related intangibles		14,726,000
Marketing-related intangibles		484,000
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
Number of years that goodwill and the amortization of intangibles deductible for tax purposes		15 years
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		74,400,000
Preliminarily allocated approximately to other intangible assets		15,200,000
Customer-related intangibles		14,700,000
Marketing-related intangibles		$ 500,000
Ironworks Consulting, L.L.C. [Member] \| Customer Related [Member]
Business Combinations (Textual) [Abstract]
Amortization period		7 years
Ironworks Consulting, L.L.C. [Member] \| Market Related [Member]
Business Combinations (Textual) [Abstract]
Amortization period		1 year
Symbiotic Engineering L.L.C. [Member]
Business Combinations (Textual) [Abstract]
Business acquisition, date of acquisition	Sep. 01, 2012
GHK Holdings Limited [Member]
Business Combinations (Textual) [Abstract]
Business acquisition, date of acquisition	Feb. 01, 2012

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

No definition available.

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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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- Details

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- Definition

Excess of purchase price over estimated fair value of tangible assets, net.

+ References

No definition available.

+ Details

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- Definition

Period of intangible and goodwill amortized for tax propose.

+ 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)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16265-109275

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

-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.

+ Details

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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.

+ Details

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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)

-URI http://asc.fasb.org/extlink&oid=7659399&loc=d3e1392-128463

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e845-128460

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Acquisition Date

-URI http://asc.fasb.org/extlink&oid=6919109

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e848-128460

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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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