Note 13 - Related Party Transactions (Details Textual) - BSLF, L.L.C. [Member] - Funding Agreement [Member] - USD ($)		9 Months Ended
Nov. 04, 2020	Sep. 30, 2020
Percentage of Remaining Litigation Proceeds Up to Three Times the Actual Funding Amount		50.00%
Percentage of Remaining Litigation Proceeds		30.00%
Agreement Termination Period (Day)		10 days
Due from Related Parties, Total		$ 762,000
Subsequent Event [Member]
Proceeds from Collections of Related Party Receivables	$ 762,000

Represents the period within which the agreement may be terminated by either party with written notice.

No definition available.

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- Definition

Represents the percentage of the remaining Litigation Proceeds 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.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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Namespace Prefix:	bcda_
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- Definition

Represents the amount of cash inflow during the period from collections of receivables from related parties.

+ References

No definition available.

+ Details

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Namespace Prefix:	bcda_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(3))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.3)
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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Balance Type:	debit
Period Type:	instant

- Details

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- Details

Name:	us-gaap_RelatedPartyTransactionAxis=bcda_FundingAgreementMember
Namespace Prefix:
Data Type:	na
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- Details

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