Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

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Gross number of share options (or share units) granted during the period.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Stockholders' Equity - Stock-Based Compensation - Additional Information (Detail)	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2019 USD ($) shares	Sep. 30, 2018 shares	Jun. 30, 2019 USD ($) $ / shares shares	Sep. 30, 2019 USD ($)
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stockholders' equity, stock split, conversion ratio			0.75
Stock options exchanged			2,456,999
Stock options issued			1,842,746
Exercise price \| $ / shares			$ 0.62
Share-based compensation expense \| $			$ 84,000
Share-based compensation arrangement, vesting period			4 years
Stock option granted	0	0
Unrecognized compensation costs \| $	$ 2,400,000			$ 2,400,000
Weighted average period				1 year 3 months 18 days