Document And Entity Information (USD $)	3 Months Ended
	Mar. 31, 2012
Entity Registrant Name	Capitol Bancorp Ltd.
Entity Central Index Key	0000840264
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Smaller Reporting Company
Entity Public Float	$ 5,260,254
Entity Common Stock, Shares Outstanding	41,038,908
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q1
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2012