| **Business Overview (Details)**                                                                   | 3 Months Ended | 9 Months Ended | 12 Months Ended |
|---------------------------------------------------------------------------------------------------|----------------|----------------|-----------------|
||
| **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%         | 97.00%         | 95.00%          | 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         |   |

| X                                                                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of persons employed by the Entity
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                 |
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| - Definition
Represents the number of integrated revenue streams areas of the entity.
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| - Definition
Represents the period for which the entity has provided professional services to U.S. Government.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                        |
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| - Definition
Represents the term of the award granted to the entity.
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No definition available.
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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.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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.
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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=6927468&loc=d3e6351-108592Reference 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=35750535&loc=d3e13531-108611Reference 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=6927468&loc=d3e6404-108592Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13537-108611
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| X                                                                                                                               |
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