Benefit Plans - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Aug. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plans [Abstract]
Employer matching contribution, percent of match	3.00%
Employer contributions to defined contribution savings plans		$ 35	$ 0

Percentage employer matches of the employee's percentage contribution matched.

No definition available.

Name:	us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration