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Equity - Additional Information (Details) - USD ($)			1 Months Ended		3 Months Ended	9 Months Ended		12 Months Ended
Equity - Additional Information (Details) - USD ($)	Jan. 01, 2020	Jan. 01, 2019	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Oct. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Proceeds from sale of common stock						$ 30,835,206	$ 0
Common stock issued, offering costs						$ 916,704	$ 0
Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Incentive units authorized for issuance				6,199,477
Share-based award, expiration date				Sep. 30, 2018
Incentive units authorized for issuance									1,293,510
Incentive Plan \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted shares vested and expected to vest					281,820	281,820
Incentive Plan \| Employee
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense						$ 22,121,591
Compensation expense not yet recognized					$ 28,645,194	$ 28,645,194
Compensation expense not yet recognized, period of recognition						2 years
Incentive Plan \| Scenario Forecast
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Incentive units authorized for issuance								1,561,485
2018 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance			4,067,007
Annual increase in reserved shares as percentage of outstanding common stock			4.00%
Stock options vested and expected to vest					4,215,253	4,215,253
Restricted stock units vested and expected to vest					110,401	110,401
Minimum \| Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based award, vesting period				1 year
Minimum \| 2018 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual increase in reserved shares of common stock			4,989,593
Maximum \| Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance			1,277,181
Share-based award, vesting period				4 years
At-the-Market Offering \| Piper Sandler
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock aggregate offering price										$ 100,000,000.0
Issuance of common stock, net of offering costs, Shares					1,163,074	1,163,074
Proceeds from sale of common stock					$ 29,900,000	$ 29,900,000
Common stock issued, offering costs					$ 900,000	$ 900,000
2018 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance	390,371	323,377	311,850
Common stock reserved for issuance represented as percentage on outstanding common stock	1.00%	1.00%
Common stock, shares issued					11,046	11,046
Common stock, shares remained available for purchase					1,014,552	1,014,552
Amount used as multiplying factor to grant common stock					$ 2,083	$ 2,083
Maximum percentage of compensation receivable by employee						15.00%
2018 ESPP \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price under ESPP as percentage of closing price of common stock						85.00%