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Proceeds from Issuance of Common Stock, Net

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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The cash inflow from the additional capital contribution to the entity.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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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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Discount rate from fair value on purchase date that participants pay for shares.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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STOCKHOLDERS' EQUITY AND SHARE-BASED COMPENSATION PLANS - Narrative (Details) $ / shares in Units, $ in Thousands			1 Months Ended	12 Months Ended
	Oct. 05, 2018 USD ($)	Apr. 20, 2018 USD ($) $ / shares shares	Jan. 31, 2020 shares	Dec. 31, 2019 USD ($) plan shares	Dec. 31, 2018 USD ($) shares
Share-based Goods and Nonemployee Services Transaction [Line Items]
Common stock, issued (in shares)				5,076,593	4,424,205
Number of share-based compensation plans \| plan				5
Proceeds from exercise of stock options \| $				$ 76	$ 3,270
2019 Equity Incentive Plan
Share-based Goods and Nonemployee Services Transaction [Line Items]
Number of shares authorized for issuance				250,000
Stock options
Share-based Goods and Nonemployee Services Transaction [Line Items]
Vesting period				4 years
Award expiration period (up to)				10 years
Employee Stock \| 2014 Employee Stock Purchase Plan
Share-based Goods and Nonemployee Services Transaction [Line Items]
Number of shares authorized for issuance				55,000
ESPP common stock discount				15.00%
Jefferies LLC
Share-based Goods and Nonemployee Services Transaction [Line Items]
Proceeds from issuance of common stock \| $	$ 60,000			$ 9,000
Common stock, issued (in shares)				259,115
Follow-Up Offering
Share-based Goods and Nonemployee Services Transaction [Line Items]
Price per share (in dollars per share) \| $ / shares		$ 75
Proceeds from issuance of common stock \| $		$ 69,000
Proceeds from issuance of common stock, net \| $		$ 64,700
Follow-Up Offering \| Common Stock
Share-based Goods and Nonemployee Services Transaction [Line Items]
Number of shares of common stock sold in offering (in shares)		920,000
Subsequent Event \| 2019 Equity Incentive Plan
Share-based Goods and Nonemployee Services Transaction [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized			600,000
Maximum \| Subsequent Event \| 2019 Equity Incentive Plan
Share-based Goods and Nonemployee Services Transaction [Line Items]
Number of shares authorized for issuance			600,540