Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2017
Schedule Of Income Taxes [Line Items]
Corporate tax rate	21.00%	31.00%	34.00%
Net operating loss carry forwards, amount		$ 4,700,000
Income (loss) of foreign subsidiaries before taxes	$ 419,000	(276,000)
Deferred tax valuation allowance against assets	1,365,000	448,000
Transition tax liability, gross		4,600,000
Decrease in transition tax liability		(1,500,000)
Income tax expense due to tax transition tax liability		3,100,000
Reduction in transition tax	342,000	(325,000)
Reduction of transition tax due to adjustment of intercompany charges	107,000
Income tax expense resulting from rate change		300,000
U.S. federal
Schedule Of Income Taxes [Line Items]
Net operating loss carry forwards, amount	$ 3,300,000
U.S. federal | Earliest Tax Year
Schedule Of Income Taxes [Line Items]
Open tax years	2016
U.S. federal | Latest Tax Year
Schedule Of Income Taxes [Line Items]
Open tax years	2018
States
Schedule Of Income Taxes [Line Items]
Net operating loss carry forwards, amount		$ 10,500,000
States | Earliest Tax Year
Schedule Of Income Taxes [Line Items]
Open tax years	2011
States | Latest Tax Year
Schedule Of Income Taxes [Line Items]
Open tax years	2018