Stock option plan and stock-based compensation (Tables)

9 Months Ended

Jun. 30, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Stock Option Activity

Stock option activity was as follows:

	Number of Options		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term	Weighted Average Intrinsic Value
					(in years)	(in thousands)
Outstanding at September 30, 2017	45,817,252		$	9.20	6.9	$	199,663
Granted	7,676,414		$	15.09
Exercised	(1,735,750	)	$	3.31
Forfeited	(3,387,668	)	$	13.05
Outstanding at June 30, 2018	48,370,248		$	10.08	6.7	$	243,060
At June 30, 2018
Options exercisable	30,582,952		$	7.70	5.4	$	226,453
Options vested and expected to vest	45,413,361		$	9.80	6.6	$	240,964

Schedule of Stock-based Compensation Expense

Total stock-based compensation expense by function category was as follows:

	Three Months Ended				Nine Months Ended
	June 30, 2018		July 1, 2017		June 30, 2018		July 1, 2017
(In thousands)
Cost of revenue	$	49	$	65	$	156	$	179
Research and development	3,651		3,529		10,417		10,136
Sales and marketing	4,391		3,899		12,414		11,172
General and administrative	2,242		2,045		6,410		5,474
Total stock-based compensation expense	$	10,333	$	9,538	$	29,397	$	26,961