Area of office.

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Number of members appointed to board of directors.

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- Definition

Related party transaction compensation percentage.

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No definition available.

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Related party transaction monthly payments in arrears.

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- Definition

Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Direct costs arising from transactions with related parties who are not affiliates or joint Ventures. These costs are categorized as cost of goods sold.

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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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Amount of sublease income excluding finance and operating lease expense.

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Amount of expense associated with supplies that were used during the current accounting period.

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Related Party Transactions (Details)	1 Months Ended				3 Months Ended
Related Party Transactions (Details)	Sep. 30, 2019 ft²	Feb. 28, 2019 ft²	Dec. 31, 2018 ft²	Aug. 31, 2018 USD ($)	Mar. 31, 2020 USD ($) board_member shares	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) shares
Related Party Transaction [Line Items]
Common stock, shares outstanding (in shares) \| shares					125,262,537		124,267,358
Pfizer
Related Party Transaction [Line Items]
Common stock, shares outstanding (in shares) \| shares					22,032,040
Pfizer \| Accrued and Other Current Liabilities
Related Party Transaction [Line Items]
Payable to related party, current					$ 0		$ 1,700,000
Pfizer \| Transition Services Agreement
Related Party Transaction [Line Items]
Related party costs					0	$ 2,700,000
Pfizer \| Transition Services Agreement \| Research and development
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party					$ 0	600,000
ByHeart
Related Party Transaction [Line Items]
Number of members appointed to board of directors \| board_member					2
ByHeart \| Sublease Agreement
Related Party Transaction [Line Items]
Area of office space \| ft²	2,907	2,180
Sublease income					$ 100,000	0
Two River \| Consulting Agreements
Related Party Transaction [Line Items]
Related party costs					100,000	$ 200,000
Bellco \| Sublease Agreement
Related Party Transaction [Line Items]
Area of office space \| ft²			1,293
Sublease, term of contract			3 years
Bellco \| Consulting Agreements
Related Party Transaction [Line Items]
Related party costs					$ 200,000
Bellco \| Consulting Agreements \| Payments Commencing January 2019
Related Party Transaction [Line Items]
Related party transaction monthly payment in arrears				$ 33,333
Bellco \| Consulting Agreements \| Payments Commencing January 2020
Related Party Transaction [Line Items]
Related party transaction monthly payment in arrears				$ 37,500
Bellco \| Consulting Agreements \| Maximum
Related Party Transaction [Line Items]
Related party transaction compensation percentage				60.00%