Stock-Based Compensation - Director Shares - Additional Information (Detail) - Director Shares [Member] $ / shares in Units, $ in Millions	1 Months Ended
Jun. 30, 2016 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued to directors \| shares	85,374
Intrinsic value of shares \| $	$ 0.4
Shares issued to directors, award date of share price \| $ / shares	$ 4.65

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration