[Line Items] for Basis of Presentation [Table]

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- Definition

Change in accounting estimate financial effect increase to revenue and operating income (loss).

+ References

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- Definition

Loss on contract services.

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No definition available.

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- Definition

Noncontrolling equity interest ownership percentage.

+ References

No definition available.

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- Definition

Unbilled receivables restructuring costs incurred.

+ References

No definition available.

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Diluted Earnings Per Share
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Contingent Stock Agreement
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
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-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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- Definition

Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 15
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6390208&loc=d3e400-110220

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- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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- Definition

Amount of each individual error being corrected in the correcting adjustment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 1.N)
-URI http://asc.fasb.org/extlink&oid=26874127&loc=d3e30840-122693

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Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Basis of Presentation [Line Items]
Loss on contract services			$ 1,000	$ 1,000
Unbilled receivables restructuring costs incurred	$ 10,000		$ 10,000		$ 11,000
Antidilutive securities	866,132	0	706,166	0
Assets held for sale	$ 2,313		$ 2,313
Accumulated depreciation	1,000		1,000
System Conversion Error [Member]
Basis of Presentation [Line Items]
Revenue to correct an error related to a system conversion.	$ (2)
Contracts Accounted for under Percentage of Completion [Member]
Basis of Presentation [Line Items]
Financial effect of change in estimate, increase to revenue and operating income (loss)			13,000	$ 7,000
Award Fees Contracts Accounted For Under Cost-Plus Type Contracts [Member] \| Contracts Accounted for under Percentage of Completion [Member]
Basis of Presentation [Line Items]
Financial effect of change in estimate, increase to revenue and operating income (loss)			$ 3,000	$ 3,000
Engility Corporation [Member]
Basis of Presentation [Line Items]
Capital stock owning percentage by parent	100.00%		100.00%
Forfeiture Support Associates LLC [Member]
Basis of Presentation [Line Items]
Non-controlling equity interest ownership percentage	50.10%		50.10%
TASC, Inc [Member]
Basis of Presentation [Line Items]
Date of acquisition			Feb. 26, 2015