Shared-Based Compensation - Reconciliation of Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2019
Number of Options (in thousands)
Beginning balance (in shares)	771,000
Granted (in shares)	210,400
Exercised (in shares)	(5,000)
Forfeitures (in shares)	(139,000)
Ending balance (in shares)	837,000
Options exercisable (in shares)	570,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Beginning balance (in dollars per share)	$ 15.17
Granted (in dollars per share)	7.93
Exercised (in dollars per share)	4.42
Forfeitures (in dollars per share)	15.61
Ending balance (in dollars per share)	13.34
Options exercisable (in dollars per share)	$ 14.24
Weighted-average remaining contractual term, outstanding	6 years 14 days
Weighted- average remaining contractual term, options exercisable	4 years 7 months
Aggregate intrinsic value, exercised	$ 7
Aggregate intrinsic value, outstanding	0
Aggregate intrinsic value, options exercisable	$ 0

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.