Collaborative Arrangements - Additional Information (Detail)	1 Months Ended
Aug. 31, 2017
Collaborative Arrangements [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contractual agreement month and year	2017-08

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.

Name:	us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration