Subsequent Events - Additional Information (Detail) - Subsequent Event [Member] shares in Millions, $ in Millions	Jul. 31, 2019 USD ($) shares
Subsequent Event [Line Items]
Number of warrants exercised \| shares	4.9
Cash proceeds \| $	$ 10.5

The cash inflow associated with the amount received from holders exercising their stock warrants.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

Name:	us-gaap_ProceedsFromWarrantExercises
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration