Subsequent Events - Additional Information (Detail) - USD ($)	Apr. 11, 2019	Mar. 31, 2019
Convertible note bears interest rate		5.00%
Convertible Debt Securities [Member] \| Subsequent Event [Member]
Consideration for a convertible note	$ 1,540
Convertible note bears interest rate	3.00%
Convertible Debt Securities [Member] \| Subsequent Event [Member] \| Qualified Financing [Member]
Debt instrument, convertible, terms of conversion feature	at a price per share equal to 80% of the price per share sold in such transaction
Convertible Debt Securities [Member] \| Subsequent Event [Member] \| Corporate Transaction [Member]
Debt instrument, convertible, terms of conversion feature	convertible note would be repaid in cash from the proceeds of such transaction in the amount of 1.5 times the outstanding principal amount, plus any accrued and unpaid interest
Convertible Debt Securities [Member] \| Subsequent Event [Member] \| Non Qualified Non Corporate [Member]
Debt instrument, convertible, terms of conversion feature	convertible note is repaid at a rate of 1.25 times the outstanding principal amount, plus accrued and unpaid interest

Description of the conversion terms of a debt instrument which may include the conversion ratio (including all potential conversion ratios if contingently adjustable), type of debt or equity security into which the debt is convertible, the dollars of debt or the number of shares into which the instrument is convertible (or potentially convertible into), the conversion period, any contingencies associated with the conversion terms, and the existence and amount of a beneficial conversion feature.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The cash outflow to acquire an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among myriad other features and characteristics.

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