Condensed Consolidated Statements of Redeemable Convertible Noncontrolling Interests and Stockholders' Equity (Parenthetical) $ in Thousands	Mar. 31, 2021 USD ($)
Statement Of Stockholders Equity [Abstract]
Repurchase of Eidos noncontrolling interests for cash and shares, transaction costs	$ 70,734

Repurchase of noncontrolling interests transaction costs.

No definition available.

Name:	bbio_RepurchaseOfNoncontrollingInterestsTransactionCosts
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant