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v3.19.3.a.u2

Business Overview (Details) | 12 Months Ended
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Sep. 30, 2019 employee business_area location | Sep. 30, 2018
Concentration Risk [Line Items] |  |
Number of market focus areas | business_area | 3 |
Number of market core competencies | business_area | 7 |
Number of employees (over) | employee | 1,900 |
Customer Concentration | Revenue Concentration | Federal Government |  |
Concentration Risk [Line Items] |  |
Concentration risk percentage | 99.00% |
Customer Concentration | Revenue Concentration | VA |  |
Concentration Risk [Line Items] |  |
Concentration risk percentage | 57.00% | 63.00%
Customer Concentration | Revenue Concentration | HHS |  |
Concentration Risk [Line Items] |  |
Concentration risk percentage | 39.00% | 34.00%
United States |  |
Concentration Risk [Line Items] |  |
Number of locations in which the entity operates (more than) | location | 30 |
Overseas |  |
Concentration Risk [Line Items] |  |
Number of locations in which the entity operates (more than) | location | 1 |

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