Description of Business (Details)	Sep. 30, 2017 customer company
Healthcare | Minimum
Description of business
Number of clients	60
Commercial, Medicaid and Medicare managed health plans | United States
Description of business
Number of largest companies in the industry sector | company	25
Commercial, Medicaid and Medicare managed health plans | United States | Minimum
Description of business
Number of largest companies in the industry sector that are customers	20
Retail
Description of business
Number of clients	35
Retail | United States
Description of business
Number of largest companies in the industry sector that are customers	8
Number of largest companies in the industry sector | company	10