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Organization, Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Details)			1 Months Ended	3 Months Ended		4 Months Ended	12 Months Ended
	Oct. 29, 2019 USD ($) shares	Oct. 11, 2019 shares	May 31, 2019 shares	Mar. 31, 2020 USD ($) Segment shares	Mar. 31, 2019 shares	May 06, 2019 shares	Dec. 31, 2019 USD ($) shares
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Description of forward stock split		2.168-for-1
Forward stock split conversion ratio		2.168
Common stock, shares authorized \| shares		50,000,000		400,000,000			400,000,000
Fair value liabilities, level 1 to level 2 transfers, amount				$ 0			$ 0
Fair value liabilities, level 2 to level 1 transfers, amount				0			0
Fair value liability, transfers into level 3				0			0
Fair value liability, transfers out of level 3				0			$ 0
Conversion of Lender Warrants into equity				318,000
Impairment losses				$ 0
Number of operating segment \| Segment				1
Unvested Shares
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Weighted-average unvested shares \| shares				4,082,104	857,595
Furniture and Fixtures
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Property and equipment, useful life				3 years
Minimum \| Computer Equipment and Related Software
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Property and equipment, useful life				2 years
Maximum \| Computer Equipment and Related Software
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Property and equipment, useful life				3 years
Lender Warrants
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Expected cash dividend yield				0.00%
Takeda Warrant \| Takeda License \| Takeda
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Shares of common stock included in calculation of basic weighted-average common shares \| shares					7,588,000
Fair Value, Recurring
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Financial assets fair value disclosure				$ 0
Fair Value, Nonrecurring
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Non-financial assets fair value disclosure				0
Non-financial liabilities fair value disclosure				0
Common Stock
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Common stock shares issued \| shares						2,524,852
Common Stock \| Takeda License
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Common stock shares issued \| shares			1,084,000
Additional Paid-in Capital
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Conversion of Lender Warrants into equity				318,000
Additional Paid-in Capital \| Lender Warrants
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Conversion of Lender Warrants into equity				$ 300,000
IPO \| Common Stock
Organization Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Common stock shares issued \| shares	10,997,630
Proceeds from Initial Public Offering (IPO)	$ 191,500,000