Note 2 - Securities (Detail) - The Amortized Cost And Approximate Fair Value Of Securities Is As Follows: (USD $)	3 Months Ended																																																																																						3 Months Ended	12 Months Ended							3 Months Ended	12 Months Ended												12 Months Ended						3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2013 US States and Political Subdivisions Debt Securities [Member] Amortized Cost [Member]	Dec. 31, 2012 US States and Political Subdivisions Debt Securities [Member] Amortized Cost [Member]	Mar. 31, 2013 US States and Political Subdivisions Debt Securities [Member] Unrealized Gains [Member]	Dec. 31, 2012 US States and Political Subdivisions Debt Securities [Member] Unrealized Gains [Member]	Mar. 31, 2013 US States and Political Subdivisions Debt Securities [Member] Fair Value [Member]	Dec. 31, 2012 US States and Political Subdivisions Debt Securities [Member] Fair Value [Member]	Mar. 31, 2013 Held To Maturity [Member] Amortized Cost [Member]	Dec. 31, 2012 Held To Maturity [Member] Amortized Cost [Member]	Mar. 31, 2013 Held To Maturity [Member] Unrealized Gains [Member]	Dec. 31, 2012 Held To Maturity [Member] Unrealized Gains [Member]	Mar. 31, 2013 Held To Maturity [Member] Fair Value [Member]	Dec. 31, 2012 Held To Maturity [Member] Fair Value [Member]	Mar. 31, 2013 Federal Reserve Bank Stock [Member] Amortized Cost [Member]		Dec. 31, 2012 Federal Reserve Bank Stock [Member] Amortized Cost [Member]		Mar. 31, 2013 Federal Reserve Bank Stock [Member] Unrealized Gains [Member]		Dec. 31, 2012 Federal Reserve Bank Stock [Member] Unrealized Gains [Member]		Mar. 31, 2013 Federal Reserve Bank Stock [Member] Unrealized Losses [Member]		Dec. 31, 2012 Federal Reserve Bank Stock [Member] Unrealized Losses [Member]		Dec. 31, 2012 Federal Reserve Bank Stock [Member] OTTI [Member]		Dec. 31, 2011 Federal Reserve Bank Stock [Member] OTTI [Member]		Mar. 31, 2013 Federal Reserve Bank Stock [Member] Fair Value [Member]		Dec. 31, 2012 Federal Reserve Bank Stock [Member] Fair Value [Member]		Mar. 31, 2013 Subsidiary Trust [Member] Amortized Cost [Member]		Dec. 31, 2012 Subsidiary Trust [Member] Amortized Cost [Member]		Mar. 31, 2013 Subsidiary Trust [Member] Unrealized Gains [Member]		Dec. 31, 2012 Subsidiary Trust [Member] Unrealized Gains [Member]		Mar. 31, 2013 Subsidiary Trust [Member] Unrealized Losses [Member]		Dec. 31, 2012 Subsidiary Trust [Member] Unrealized Losses [Member]		Dec. 31, 2012 Subsidiary Trust [Member] OTTI [Member]		Dec. 31, 2011 Subsidiary Trust [Member] OTTI [Member]		Mar. 31, 2013 Subsidiary Trust [Member] Fair Value [Member]		Dec. 31, 2012 Subsidiary Trust [Member] Fair Value [Member]		Mar. 31, 2013 US Government Agencies Debt Securities [Member] Amortized Cost [Member]	Dec. 31, 2012 US Government Agencies Debt Securities [Member] Amortized Cost [Member]	Mar. 31, 2013 US Government Agencies Debt Securities [Member] Unrealized Gains [Member]	Dec. 31, 2012 US Government Agencies Debt Securities [Member] Unrealized Gains [Member]	Mar. 31, 2013 US Government Agencies Debt Securities [Member] Unrealized Losses [Member]	Dec. 31, 2012 US Government Agencies Debt Securities [Member] Unrealized Losses [Member]	Mar. 31, 2013 US Government Agencies Debt Securities [Member] Fair Value [Member]	Dec. 31, 2012 US Government Agencies Debt Securities [Member] Fair Value [Member]	Mar. 31, 2013 US States and Political Subdivisions Debt Securities [Member] Amortized Cost [Member]	Dec. 31, 2012 US States and Political Subdivisions Debt Securities [Member] Amortized Cost [Member]	Mar. 31, 2013 US States and Political Subdivisions Debt Securities [Member] Unrealized Gains [Member]	Dec. 31, 2012 US States and Political Subdivisions Debt Securities [Member] Unrealized Gains [Member]	Mar. 31, 2013 US States and Political Subdivisions Debt Securities [Member] Unrealized Losses [Member]	Mar. 31, 2013 US States and Political Subdivisions Debt Securities [Member] Fair Value [Member]	Dec. 31, 2012 US States and Political Subdivisions Debt Securities [Member] Fair Value [Member]	Mar. 31, 2013 Corporate Debt Securities [Member] Amortized Cost [Member]	Dec. 31, 2012 Corporate Debt Securities [Member] Amortized Cost [Member]	Mar. 31, 2013 Corporate Debt Securities [Member] Unrealized Gains [Member]	Dec. 31, 2012 Corporate Debt Securities [Member] Unrealized Gains [Member]	Mar. 31, 2013 Corporate Debt Securities [Member] Fair Value [Member]	Dec. 31, 2012 Corporate Debt Securities [Member] Fair Value [Member]	Mar. 31, 2013 Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Amortized Cost [Member]	Dec. 31, 2012 Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Amortized Cost [Member]	Mar. 31, 2013 Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Unrealized Gains [Member]	Dec. 31, 2012 Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Unrealized Gains [Member]	Mar. 31, 2013 Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Unrealized Losses [Member]	Mar. 31, 2013 Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Fair Value [Member]	Dec. 31, 2012 Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Fair Value [Member]	Mar. 31, 2013 Residential Mortgage Backed Securities [Member] Amortized Cost [Member]	Dec. 31, 2012 Residential Mortgage Backed Securities [Member] Amortized Cost [Member]	Mar. 31, 2013 Residential Mortgage Backed Securities [Member] Unrealized Gains [Member]	Dec. 31, 2012 Residential Mortgage Backed Securities [Member] Unrealized Gains [Member]	Mar. 31, 2013 Residential Mortgage Backed Securities [Member] OTTI [Member]	Dec. 31, 2012 Residential Mortgage Backed Securities [Member] OTTI [Member]	Mar. 31, 2013 Residential Mortgage Backed Securities [Member] Fair Value [Member]	Dec. 31, 2012 Residential Mortgage Backed Securities [Member] Fair Value [Member]	Mar. 31, 2013 Asset-backed Securities [Member] Amortized Cost [Member]	Dec. 31, 2012 Asset-backed Securities [Member] Amortized Cost [Member]	Mar. 31, 2013 Asset-backed Securities [Member] Unrealized Gains [Member]	Dec. 31, 2012 Asset-backed Securities [Member] Unrealized Gains [Member]	Mar. 31, 2013 Asset-backed Securities [Member] OTTI [Member]	Dec. 31, 2012 Asset-backed Securities [Member] OTTI [Member]	Mar. 31, 2013 Asset-backed Securities [Member] Fair Value [Member]	Dec. 31, 2012 Asset-backed Securities [Member] Fair Value [Member]	Mar. 31, 2013 CRA Funds [Member] Amortized Cost [Member]	Dec. 31, 2012 CRA Funds [Member] Amortized Cost [Member]	Mar. 31, 2013 CRA Funds [Member] Unrealized Gains [Member]	Dec. 31, 2012 CRA Funds [Member] Unrealized Gains [Member]	Mar. 31, 2013 CRA Funds [Member] Fair Value [Member]	Dec. 31, 2012 CRA Funds [Member] Fair Value [Member]	Dec. 31, 2012 Securities (Assets) [Member] Amortized Cost [Member]	Dec. 31, 2012 Securities (Assets) [Member] Unrealized Gains [Member]	Dec. 31, 2012 Securities (Assets) [Member] Unrealized Losses [Member]	Dec. 31, 2012 Securities (Assets) [Member] OTTI [Member]	Dec. 31, 2012 Securities (Assets) [Member] Fair Value [Member]	Mar. 31, 2013 Amortized Cost [Member]	Dec. 31, 2012 Amortized Cost [Member]	Mar. 31, 2013 Unrealized Gains [Member]	Mar. 31, 2013 Unrealized Losses [Member]	Mar. 31, 2013 OTTI [Member]	Mar. 31, 2013 Fair Value [Member]	Dec. 31, 2012 Fair Value [Member]
Debt securities
Amortized Cost																																																							$ 81,385,000	$ 70,892,000							$ 14,618,000	$ 12,810,000						$ 6,074,000	$ 6,080,000					$ 61,558,000	$ 56,572,000						$ 684,000	$ 718,000							$ 176,000	$ 187,000							$ 14,204,000	$ 14,128,000					$ 161,387,000					$ 178,699,000
Gains																																																									240,000	362,000							426,000	579,000						265,000	270,000					1,225,000	1,369,000						353,000	330,000							148,000	129,000							131,000	233,000				3,272,000						2,788,000
Unrealized Losses																																																											(206,000)	(73,000)							(49,000)													(51,000)																											(73,000)						(306,000)
OTTI	509,000																																																																																						(342,000)	(365,000)							(167,000)	(173,000)												(538,000)						(509,000)
Fair Value	166,337,000																																																												81,419,000	71,181,000						14,995,000	13,389,000					6,339,000	6,350,000						62,732,000	57,941,000							695,000	683,000							157,000	143,000					14,335,000	14,361,000					164,048,000						180,672,000
Securities held-to-maturity
Amortized Cost			4,046,000	4,046,000					4,046,000	4,046,000
Gains					624,000	711,000					624,000	711,000
Fair Value	4,670,000	4,757,000					4,670,000	4,757,000					4,670,000	4,757,000
Amortized Cost	5,413,000														4,330,000	[1],[2]	4,509,000	[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]	4,330,000	[1],[2]	4,509,000	[1],[2]	1,083,000	[3]	1,083,000	[3]		[3]		[3]		[3]		[3]		[3]		[3]	1,083,000	[3]	1,083,000	[3]																																																								5,413,000	5,592,000				5,413,000	5,592,000
Fair Value	5,413,000														4,330,000	[1],[2]	4,509,000	[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]	4,330,000	[1],[2]	4,509,000	[1],[2]	1,083,000	[3]	1,083,000	[3]		[3]		[3]		[3]		[3]		[3]		[3]	1,083,000	[3]	1,083,000	[3]																																																								5,413,000	5,592,000				5,413,000	5,592,000
Gains	5,413,000														4,330,000	[1],[2]	4,509,000	[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]	4,330,000	[1],[2]	4,509,000	[1],[2]	1,083,000	[3]	1,083,000	[3]		[3]		[3]		[3]		[3]		[3]		[3]	1,083,000	[3]	1,083,000	[3]																																																								5,413,000	5,592,000				5,413,000	5,592,000
Unrealized Losses	5,413,000														4,330,000	[1],[2]	4,509,000	[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]	4,330,000	[1],[2]	4,509,000	[1],[2]	1,083,000	[3]	1,083,000	[3]		[3]		[3]		[3]		[3]		[3]		[3]	1,083,000	[3]	1,083,000	[3]																																																								5,413,000	5,592,000				5,413,000	5,592,000
OTTI	$ 5,592,000														$ 4,330,000	[1],[2]	$ 4,509,000	[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]		[1],[2]	$ 4,330,000	[1],[2]	$ 4,509,000	[1],[2]	$ 1,083,000	[3]	$ 1,083,000	[3]		[3]		[3]		[3]		[3]		[3]		[3]	$ 1,083,000	[3]	$ 1,083,000	[3]																																																								$ 5,413,000	$ 5,592,000				$ 5,413,000	$ 5,592,000

[1] FHLB stock held by the Banks is subject to certain restrictions under a credit policy of the FHLB dated May 1, 1997. Redemption of FHLB stock is dependent upon repayment of borrowings, if any, from the FHLB.

[2] Federal Reserve Bank stock held by MetroBank is subject to certain restrictions under Federal Reserve Bank Policy.

[3] The Company's ownership of common securities of MCBI Trust I is carried at cost.