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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		12 Months Ended
	Mar. 31, 2020 USD ($) Customer	Mar. 31, 2019 USD ($) Customer	Dec. 31, 2019 USD ($) Customer
Summary Of Significant Accounting Policies [Line Items]
Foreign currency, losses from remeasurements	$ 85,000
Receivables from contract with customers	6,371,000		$ 6,555,000
Contract liability	444,000		365,000
Contract with customer liability, revenue recognized	242,000	$ 33,000
Practical expedient not to disclose amount of transaction price allocated to unsatisfied performance obligations		true
Other Current Assets
Summary Of Significant Accounting Policies [Line Items]
Contract assets from contract with customers	$ 150,000		$ 150,000
Customer Concentration Risk \| Revenue
Summary Of Significant Accounting Policies [Line Items]
Number of customers \| Customer		2
Customer Concentration Risk \| Revenue \| Customer One
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		20.00%
Customer Concentration Risk \| Revenue \| Customer Two
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		11.00%
Customer Concentration Risk \| Revenue \| Minimum
Summary Of Significant Accounting Policies [Line Items]
Number of customers \| Customer	0
Concentration risk, percentage	10.00%
Customer Concentration Risk \| Accounts Receivable \| Minimum
Summary Of Significant Accounting Policies [Line Items]
Number of customers \| Customer	0		0
Concentration risk, percentage	10.00%		10.00%