Business Overview (Details)	6 Months Ended
Mar. 31, 2016 employee business_area location
Concentration Risk [Line Items]
Minimum period for which entity has provided professional services to the U.S. Government (years)	25 years
Number of employees (employee) \| employee	1,250
Minimum number of locations in which entity operates (location) \| location	30
Number of broad integrated revenue streams \| business_area	2
US Government [Member] \| Revenue concentration \| Customer concentration
Concentration Risk [Line Items]
Concentration risk percentage (percent)	100.00%
DVA \| Revenue concentration \| Customer concentration
Concentration Risk [Line Items]
Concentration risk percentage (percent)	96.00%
DVA \| Minimum
Concentration Risk [Line Items]
Term of government contract	1 year
DVA \| Maximum
Concentration Risk [Line Items]
Term of government contract	3 years

Number of persons employed by the Entity

No definition available.

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- Definition

Represents the number of integrated revenue streams areas of the entity.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the period for which the entity has provided professional services to U.S. Government.

+ References

No definition available.

+ Details

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- Definition

Represents the term of the award granted to the entity.

+ References

No definition available.

+ Details

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- Definition

Represents the minimum number of locations the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6404-108592

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13537-108611

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- Details

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- Details

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- Details

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