Collaborative Arrangement - Additional Information (Detail) - Abbott [Member] - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront fee received			$ 25,000,000		$ 25,000,000
Collaboration revenue recognized	$ 2,000,000	$ 1,700,000	5,900,000	$ 2,200,000
Upfron fee payment included in deferred revenue	14,700,000		14,700,000		$ 20,600,000
Maximum [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborative arrangement additional potential milestone payments receivable	$ 67,000,000		$ 67,000,000