The amount of initial transaction price.

No definition available.

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- Definition

The amount of licenses fee recognized during the period.

+ References

No definition available.

+ Details

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- Definition

The amount of second milestone payment recognized during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The amount of license fee recognized during the period.

+ References

No definition available.

+ Details

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- Definition

The amount of license fee receivable in first installment during the period.

+ References

No definition available.

+ Details

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- Definition

The amount of license fee receivable in second installment during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The amount of commercialization milestones payment to be received under collaborative arrangements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The amount of development milestone payment received to date.

+ References

No definition available.

+ Details

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- Definition

The amount of development milestones payment to be received under collaborative arrangements.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of future development and commercialization milestone under collaborative arrangements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The amount of upfront payments and development and sales milestones payment to be received under collaborative arrangements.

+ References

No definition available.

+ Details

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- Definition

Number of compounds inhibiting the first undisclosed target.

+ References

No definition available.

+ Details

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- Definition

Number of development candidates.

+ References

No definition available.

+ Details

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- Definition

Number of pre-clinical study-ready compounds.

+ References

No definition available.

+ Details

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- Definition

Number of separate collaborative agreements.

+ References

No definition available.

+ Details

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- Definition

Amount of change in estimate of revenue to be recognized during the period.

+ References

No definition available.

+ Details

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- Definition

Term of agreement.

+ References

No definition available.

+ Details

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- Definition

Term of payment of first installment fee.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

Represents the threshold percentage of net sales for tiered royalties.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Transaction price allocated to partially unsatisfied performance obligations.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Balance Type:	credit
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- Definition

Cash received from licensees for license fees during the current period.

+ References

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-Name Accounting Standards Codification
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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Collaboration and Licensing Agreements - Additional Information (Details)	1 Months Ended				3 Months Ended		12 Months Ended	29 Months Ended
	Nov. 30, 2019 USD ($) item	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Nov. 30, 2017 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue					$ 1,213,000
Unbilled revenue					750,000			$ 750,000	$ 750,000
Other
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue					38,000
2019 KKC Agreement \| Kyowa Kirin Co. Ltd
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of pre-clinical study-ready compounds \| item	2
Number of compounds inhibiting the first undisclosed target \| item	1
Upfront payment recognized	$ 10,000,000
License fee receivable, first installment	$ 5,000,000
Term of payment of license fee, first installment	30 days
License fee receivable, Second instalment	$ 5,000,000
Term of agreement	2 years
Initial transaction price	$ 10,000,000
Revenue					1,200,000
Change in estimates					0
Transaction price allocated to partially unsatisfied performance obligations					8,400,000			8,400,000
Uncharged license fees					3,400,000			3,400,000
2019 KKC Agreement \| Kyowa Kirin Co. Ltd \| Minimum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of development candidates \| item	1
Number of separate collaborative agreements \| item	1
2017 KKC Agreement \| Kyowa Kirin Co. Ltd
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront payment recognized				$ 30,000,000
Uncharged license fees									1,000,000
Upfront payment received				30,000,000
Unbilled revenue									$ 5,000,000
Development milestones Received								$ 5,000,000
Commercialization milestones				78,300,000
2017 KKC Agreement \| Kyowa Kirin Co. Ltd \| Maximum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Development milestones				$ 55,000,000
2017 KKC Agreement \| Kyowa Kirin Co. Ltd \| Other
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue					38,000	$ 0
XuanZhu Agreement \| XuanZhu
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue					0
Upfront payment received	$ 750,000
License fee recognized	1,500,000
Second milestone payment	$ 750,000
Fosun Agreement \| Fosun Pharma
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront payment recognized			$ 12,000,000				$ 12,000,000
Revenue					0	0
Future development milestones							$ 110,000,000
Fosun Agreement \| Fosun Pharma \| Maximum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Threshold percentage of net sales for tiered royalties			20.00%
Knight Agreement \| Knight
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue					$ 0	$ 0
Total payments, including an up-front payment and development and sales milestones to be received		$ 17,600,000