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Represents the amount provided to fund research program.

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No definition available.

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Represents the milestone payments per product.

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Represents the cash outflow from payments made to related party during the year.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholders and which takes precedence over common stockholders in the event of liquidation.

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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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No definition available.

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Related Party Transactions - (Details) - USD ($)			1 Months Ended		9 Months Ended	12 Months Ended
Related Party Transactions - (Details) - USD ($)	Nov. 05, 2018	Nov. 02, 2018	Nov. 30, 2018	Dec. 31, 2015	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Related Party Transactions
Equity investment		$ 15,000,000			$ 31,000,000	$ 122,223,000	$ 25,000,000
Series B-3 preferred stock
Related Party Transactions
Equity investment	$ 93,400,000		$ 15,000,000
Lilly Agreement
Related Party Transactions
Upfront non-refundable payment received		25,000,000
Equity investment		$ 15,000,000
Lilly Agreement \| Lilly
Related Party Transactions
Upfront non-refundable payment received			25,000,000
Lilly Agreement \| Lilly \| Series B-3 preferred stock
Related Party Transactions
Equity investment			$ 15,000,000
Consulting Agreement \| Scientific Founder
Related Party Transactions
Monthly consulting fees				$ 5,000
Amount due to related party						120,000
Yale License Agreement \| Yale University
Related Party Transactions
Milestone payments per product				3,000,000
Sponsored Research Agreement \| Yale University
Related Party Transactions
Amount provided to fund research program				$ 12,400,000
Aggregate payments made						7,400,000
Payments made to related party						$ 2,500,000	$ 2,100,000