Anti-dilutive Security not Included In Diluted per Share Calculations (Detail) - shares	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti dilutive securities	1,623,065	1,038,432
Options To Purchase Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti dilutive securities	1,612,871	1,026,393
Common Stock Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti dilutive securities	10,194	12,039

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Name:	us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration