Balance sheet components - Schedule of Deferred Contract Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
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