Goodwill and Intangible Assets (Details) $ in Thousands	6 Months Ended
Jun. 30, 2018 USD ($) Segment
Goodwill and Intangible Assets [Abstract]
Number of reporting units \| Segment	2
Number of operating segments \| Segment	2
Goodwill [Roll Forward]
Goodwill, Beginning Balance	$ 8,431
Goodwill, Acquired During Period	5,087
Goodwill, Ending Balance	13,518
Performance Improvement Solutions [Member]
Goodwill [Roll Forward]
Goodwill, Beginning Balance	0
Goodwill, Acquired During Period	5,087
Goodwill, Ending Balance	5,087
Nuclear Industry Training and Consulting [Member]
Goodwill [Roll Forward]
Goodwill, Beginning Balance	8,431
Goodwill, Acquired During Period	0
Goodwill, Ending Balance	$ 8,431

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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- References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

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- Definition

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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