The cash outflow for payment of underwriting discounts and commissions.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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The cash outflow for cost incurred directly with the issuance of an equity security.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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The cash inflow associated with the amount received from entity's first offering of stock to the public.

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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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- Definition

Number of new stock issued 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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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Nature of the Business - (Details) $ / shares in Units, $ in Thousands			9 Months Ended
	May 13, 2019 USD ($) $ / shares shares	May 03, 2019	Sep. 30, 2019 USD ($) $ / shares shares	Jun. 30, 2019 $ / shares	Dec. 31, 2018 $ / shares shares	Dec. 31, 2017 $ / shares shares
Nature of the Business
Reverse stock split ratio		0.1245
Proceeds from issuance of shares, net \| $			$ 77,264
Common stock, shares outstanding	15,560,569		22,739,345		1,374,812	1,369,212
Preferred stock, shares outstanding	0		0		0
Common stock, number of shares authorized	100,000,000		100,000,000		158,745,671	84,045,455
Common stock, par value per share \| $ / shares	$ 0.001		$ 0.001	$ 0.001	$ 0.001	$ 0.001
Preferred stock, number of shares authorized	10,000,000		10,000,000		0
Preferred stock, par value per share \| $ / shares	$ 0.001		$ 0.001		$ 0.001
IPO
Nature of the Business
Issuance of stock (in shares)	5,750,000
Share price \| $ / shares	$ 15.00
Proceeds from issuance of shares, net \| $	$ 77,000
Underwriting discounts and commissions \| $	6,000
Offering expenses \| $	$ 3,400