Balance sheet components - Schedule of Deferred Contract Costs (Details) - USD ($) $ in Thousands  | 
12 Months Ended | |
|---|---|---|
Sep. 30, 2019  | 
Sep. 30, 2018  | 
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| Financial information for each of the Company's business segments | ||
| Deferred contract costs | $ 43,140 | $ 29,941 | 
| Less: Accumulated amortization | (24,219) | (15,561) | 
| Total Deferred contract costs, net | 18,921 | $ 14,380 | 
| Gross increase to contract costs | 14,500 | |
| Amortization of deferred contract costs | 9,900 | |
| U.S. Health and Human Services | ||
| Financial information for each of the Company's business segments | ||
| Impairment loss on contract costs | $ 3,700 | 
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- Definition Capitalized Contract Cost, Additions No definition available. 
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- Definition Amount of accumulated amortization of asset recognized from cost incurred to obtain or fulfill contract with customer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount, before accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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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. No definition available. 
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- Details 
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