Change in Accounting Principle (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012		Jun. 30, 2013	Jun. 30, 2012		Dec. 31, 2012		Dec. 31, 2011
Consolidated Balance Sheets [Abstract]
Portfolio loans, less allowance for loan losses	$ 868,524			$ 868,524			$ 1,053,052
Total assets	1,232,700			1,232,700			1,621,302
Accrued interest on deposits and other liabilities	7,649			7,649			5,944
Total liabilities	1,369,378			1,369,378			1,758,850
Retained-earnings deficit	(417,189)			(417,189)			(424,022)
Total Capitol Bancorp Limited stockholders' equity deficit	(120,533)			(120,533)			(127,301)
Total equity deficit	(136,678)	(126,335)		(136,678)	(126,335)		(137,548)		(104,519)
Consolidated Statements of Operations [Abstract]
Costs (income) associated with foreclosed properties and other real estate owned	(92)	4,377		1,106	7,344
Total noninterest expense	15,109	24,235		34,076	45,722
Loss before income tax benefit	10,891	(8,430)		6,703	(14,952)
Loss from continuing operations	10,891	(8,431)		8,250	(14,908)
Net loss	8,979	(9,928)		6,472	(18,159)
Net loss attributable to Capitol Bancorp Limited	9,300	(9,589)		6,833	(16,801)
Net loss per common share attributable to Capitol Bancorp Limited	$ 0.23	$ (0.23)		$ 0.17	$ (0.41)
As Previously Reported [Member]
Consolidated Balance Sheets [Abstract]
Portfolio loans, less allowance for loan losses							1,143,212
Total assets							1,618,252
Accrued interest on deposits and other liabilities							9,779
Total liabilities							1,762,368
Retained-earnings deficit							(430,590)
Total Capitol Bancorp Limited stockholders' equity deficit							(133,869)
Total equity deficit							(144,116)
Consolidated Statements of Operations [Abstract]
Costs (income) associated with foreclosed properties and other real estate owned		6,055			11,055
Total noninterest expense		28,024			53,774
Loss before income tax benefit		(10,692)			(19,750)
Loss from continuing operations		(10,693)			(19,706)
Net loss		(10,678)			(19,609)
Net loss attributable to Capitol Bancorp Limited		(10,339)			(18,251)
Net loss per common share attributable to Capitol Bancorp Limited		$ (0.25)			$ (0.44)
Reclassification of Discontinued Operations [Member]
Consolidated Balance Sheets [Abstract]
Portfolio loans, less allowance for loan losses							(93,210)	[1]
Total assets							0	[1]
Accrued interest on deposits and other liabilities							(317)	[1]
Total liabilities							0	[1]
Retained-earnings deficit							0	[1]
Total Capitol Bancorp Limited stockholders' equity deficit							0	[1]
Total equity deficit							0	[1]
Consolidated Statements of Operations [Abstract]
Costs (income) associated with foreclosed properties and other real estate owned		(928)	[1]		(2,261)	[1]
Total noninterest expense		(3,039)	[1]		(6,602)	[1]
Loss before income tax benefit		1,512	[1]		3,348	[1]
Loss from continuing operations		1,512	[1]		3,348	[1]
Effect of Change In Accounting Principle [Member]
Consolidated Balance Sheets [Abstract]
Portfolio loans, less allowance for loan losses							3,050
Total assets							3,050
Accrued interest on deposits and other liabilities							(3,518)
Total liabilities							(3,518)
Retained-earnings deficit							6,568
Total Capitol Bancorp Limited stockholders' equity deficit							6,568
Total equity deficit							6,568
Consolidated Statements of Operations [Abstract]
Costs (income) associated with foreclosed properties and other real estate owned		(750)			(1,450)
Total noninterest expense		(750)			(1,450)
Loss before income tax benefit		750			1,450
Loss from continuing operations		750			1,450
Net loss		750			1,450
Net loss attributable to Capitol Bancorp Limited		750			1,450
As Adjusted [Member]
Consolidated Statements of Operations [Abstract]
Costs (income) associated with foreclosed properties and other real estate owned		4,377			7,344
Total noninterest expense		24,235			45,722
Loss before income tax benefit		(8,430)			(14,952)
Loss from continuing operations		(8,431)			(14,908)
Net loss		(9,928)			(18,159)
Net loss attributable to Capitol Bancorp Limited		$ (9,589)			$ (16,801)
Net loss per common share attributable to Capitol Bancorp Limited		$ (0.23)			$ (0.41)

[1] For comparative purposes, original balances as previously reported have also been adjusted to exclude amounts related to discontinued operations.