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Maximum potential performance based milestone awards to be settled in shares.

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Number of employees for replacement awards.

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Number of options issued in exchange of subsidiary equity.

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Number of performance-based restricted stock awards issued in exchange of subsidiary equity.

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Number of performance-based stock options issued in exchange of subsidiary equity.

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Number of restricted stock awards issued in exchange of subsidiary equity.

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Number of restricted stock units issued in exchange of subsidiary equity.

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Number of shares issued in exchange of subsidiary equity.

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Performance-based milestone awards.

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Performance based milestone awards compensation expense.

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Performance based milestone awards compensation expense settled with equity.

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Performance based milestone awards period for recognition.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate number of common shares reserved for future issuance.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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 accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of grantees affected by modification of award under share-based payment arrangement.

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Amount of cost expensed and capitalized for award under share-based payment arrangement.

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Stock-Based Compensation - Additional Information (Details)			3 Months Ended		9 Months Ended
	Nov. 18, 2020 USD ($) Grantee shares	Apr. 22, 2020 USD ($) Grantee shares	Sep. 30, 2021 USD ($) Employee shares	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) Employee $ / shares shares	Sep. 30, 2020 USD ($)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation			$ 16,130,000	$ 17,699,000	$ 83,061,000	$ 46,313,000
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common shares reserved for future issuance \| shares			4,235,440		4,235,440
Weighted-average grand date fair value of options granted \| $ / shares					$ 16.29
2020 Stock and Equity Award Exchange Program
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation cost associated with milestone awards					$ 25,800,000
Maximum potential milestone performance-based awards to be settled in fully-vested RSA	$ 11,700,000	$ 183,400,000
Performance-based milestone awards		$ 17,400,000
2020 Stock and Equity Award Exchange Program \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance-based milestone awards period for recognition		8 months 12 days
2020 Stock and Equity Award Exchange Program \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance-based milestone awards period for recognition		1 year 8 months 12 days
Employee Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average grand date fair value of options granted \| $ / shares					$ 31.03
Employee Stock Options \| 2020 Stock and Equity Award Exchange Program
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options issued in exchange of subsidiary equity \| shares	70,436	1,268,110
Restricted Stock Awards \| 2020 Stock and Equity Award Exchange Program
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of RSAs issued in exchange of subsidiary equity \| shares		50,145
Performance based milestone awards compensation expense settled with equity			$ 700,000		$ 6,700,000
Performance-Based RSAs \| 2020 Stock and Equity Award Exchange Program
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Performance-Based RSAs issued in exchange of subsidiary equity \| shares		22,611
Performance-Based Stock Options \| 2020 Stock and Equity Award Exchange Program
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Performance-Based stock options issued in exchange of subsidiary equity \| shares	10,772
A&R 2019 Plan \| 2020 Stock and Equity Award Exchange Program
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of grantees \| Grantee	16	149
Number of shares issued in exchange of subsidiary equity \| shares	24,924	554,064
A&R 2019 Plan \| Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common shares reserved for future issuance \| shares			7,977,872		7,977,872
2019 Inducement Plan \| Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common shares reserved for future issuance \| shares			8,938		8,938
Eidos Award Exchange Plan \| Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common shares reserved for future issuance \| shares			2,802,644		2,802,644
A&R 2019 Plan and 2019 Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average grand date fair value of options granted \| $ / shares					$ 31.03
Total intrinsic value of options exercised					$ 50,400,000
A&R 2019 Plan and 2019 Inducement Plan \| 2020 Stock and Equity Award Exchange Program
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation					$ 23,427,000
A&R 2019 Plan and 2019 Inducement Plan \| Employee Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period					4 years
Stock-based compensation			$ 8,100,000		$ 21,900,000
Unrecognized compensation cost			71,600,000		$ 71,600,000
Unrecognized compensation cost, period for recognition					2 years 1 month 6 days
A&R 2019 Plan and 2019 Inducement Plan \| Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation			1,486,000		$ 28,181,000
Unrecognized compensation cost, period for recognition					2 years 1 month 6 days
Unrecognized compensation cost			11,700,000		$ 11,700,000
A&R 2019 Plan and 2019 Inducement Plan \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation			6,400,000		$ 16,800,000
Unrecognized compensation cost, period for recognition					3 years 1 month 6 days
Unrecognized compensation cost			80,000,000.0		$ 80,000,000.0
BridgeBio Equity Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance-based milestone awards compensation expense			100,000		3,300,000
Stock-based compensation			$ 15,490,000	13,869,000	$ 78,216,000	37,454,000
Eidos
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation				$ 3,440,000		$ 8,085,000
Eidos \| Eidos 2016 and 2018 Plans
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options issued in exchange of subsidiary equity \| shares					2,776,672
Number of RSUs issued in exchange of subsidiary equity \| shares					25,972
Number of employees for replacement awards \| Employee			88		88
Incremental compensation cost for awards modification			$ 0		$ 0