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Percentage of accumulated dividends payable in common stock upon IPO.

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Percentage of dividend payable in cash.

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Percentage of dividends accrued.

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Percentage of increase in accrued dividend.

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Temporary equity covenant description.

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Temporary equity maturity month and year.

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Temporary equity penalty term.

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Temporary equity penalty term upon full exercise of warrant.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

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The cash outflow for reacquisition of callable preferred stock.

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The percentage rate used to calculate dividend payments on preferred stock.

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

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Number of new stock issued during the period.

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Value of accretion of temporary equity during the period due to unpaid dividends.

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Value of accretion of temporary equity to its redemption value during the period.

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Aggregate amount of redemption requirements for each class or type of redeemable stock classified as temporary equity for each of the five years following the latest balance sheet date. The redemption requirement does not constitute an unconditional obligation that will be settled in a variable number of shares constituting a monetary value predominantly indexed to (a) a fixed monetary amount known at inception, (b) an amount inversely correlated with the residual value of the entity, or (c) an amount determined by reference to something other than the fair value of issuer's stock. Does not include mandatorily redeemable stock. The exception is if redemption is required upon liquidation or termination of the reporting entity.

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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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The per share liquidation preference (or restrictions) of stock classified as temporary equity that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Per share amount of par value or stated value of stock classified as temporary equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable.

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The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Redeemable Series A-1 Preferred Stock - Additional Information (Details) - USD ($)				3 Months Ended						9 Months Ended	12 Months Ended
	Jul. 27, 2020	Jul. 26, 2020	Apr. 13, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Dec. 31, 2019	Oct. 31, 2018	Oct. 19, 2018
Temporary Equity [Line Items]
Share price				$ 16.36			$ 27.30			$ 16.36
Payments for repurchase of redeemable preferred stock in cash	$ 131,800,000									$ 131,821,000
Common stock shares sold under IPO	1,786,739
Percentage of dividends paid in cash			14.20%
Fair value changes in the contingent put option				$ (26,265,000)						$ (19,240,000)
Redeemable Series A-1 Preferred Stock
Temporary Equity [Line Items]
Temporary equity, shares issued				0						0	12,000		12,000
Temporary equity, par value per share				$ 0.0001						$ 0.0001	$ 0.0001		$ 0.0001
Warrants to purchase common stock												534,240	534,240
Temporary equity, liquidation preference per share													$ 10,000
Temporary equity, maturity month and year			2024-10
Temporary equity, penalty term			3 years
Temporary equity, penalty term upon full exercise of warrant			2 years
Percentage of increase in accrued dividend			1.00%
Total accreted value		$ 40,800,000		$ 6,542,000	$ 5,644,000	$ 5,415,000	$ 5,030,000	$ 4,777,000	$ 4,534,000
Accretion of dividends		$ 24,300,000
Temporary equity, covenant description										The Redeemable Series A-1 Preferred Stock contained restrictive covenants. As of December 31, 2019, the Company was subject to a consolidated total leverage ratio (including the outstanding principal and accrued dividend on the Redeemable Series A-1 Preferred Stock) limit of less than 10.0 times as of the end of any fiscal quarter ending until maturity. The Company was in compliance with the covenants as of December 31, 2019.
Percentage of dividends paid in cash										15.00%
Percentage of dividends accrued										14.20%
Accrued and unpaid dividends											$ 21,900,000
Fair value changes in the contingent put option	$ 12,100,000										$ 7,100,000
Changes in fair value				$ 26,300,000						$ 19,200,000
Redeemable Series A-1 Preferred Stock \| Maximum [Member]
Temporary Equity [Line Items]
Temporary equity, aggregate amount of redemption requirement			$ 50,000,000
Percentage of accumulated dividends payable in common stock upon IPO			50.00%
Share price			$ 31.60
Percentage of dividend payable in cash			15.00%
Redeemable Series A-1 Preferred Stock \| Minimum
Temporary Equity [Line Items]
Percentage of dividend payable in cash			9.00%