Note 11 - Related Party Transactions (Details Textual) - BSLF, L.L.C. [Member] - Funding Agreement [Member]	6 Months Ended
Jun. 30, 2021
Percentage of Remaining Litigation Proceeds Up to Three Times the Actual Funding Amount	50.00%
Percentage of Remaining Litigation Proceeds	30.00%

Represents the percentage of the remaining Litigation Proceeds, up to three times the Actual Funding Amount, to be added to any taxes paid by or imposed with request to claims and an amount, without reduction, set-off or counterclaim, equal to the amount actually paid pursuant to the agreement.

No definition available.

Name:	bcda_PercentageOfRemainingLitigationProceedsUpToThreeTimesTheActualFundingAmount
Namespace Prefix:	bcda_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration