Segment Information, Reconciliation of Assets from Segment to Consolidated (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) Segment	Dec. 31, 2016 USD ($)
Segment Information [Abstract]
Number of reportable business segments \| Segment	2
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 56,855	$ 53,656
Minimum [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Contract term	0 months
Maximum [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Contract term	2 years
Performance Improvement Solutions [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 34,107	42,383
Nuclear Industry Training and Consulting [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	22,748	11,249
Intersegment Eliminations [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 0	$ 24

Refers to the range of expiration dates contract or contracts expire. May be presented in a variety of ways (for example: year only, month and year, day, month and year, number of months, and number of years).

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

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- References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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