Summary of Significant Accounting Policies - Revenue Recognition (Details)	12 Months Ended
Dec. 31, 2018 Agreement
Accounting Policies [Abstract]
Number of contractual arrangement	2

Number of contract generating grant and contract revenue.

No definition available.

Name:	cbli_NumberOfContractGeneratingGrantAndContractRevenue
Namespace Prefix:	cbli_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration