Note 4 - Loans/Leases Receivable (Details) - Composition of the Loan/Lease Portfolio (USD $)	Sep. 30, 2013		Jun. 30, 2013	Dec. 31, 2012		Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases	$ 1,539,383,825			$ 1,287,387,639
Less allowance for estimated losses on loans/leases	(22,062,389)		(21,156,379)	(19,925,204)		(19,416,748)	(18,724,535)	(18,789,262)
Loans/leases net of allowance for estimated losses	1,517,321,436			1,267,462,435
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases	471,256,974			394,244,252
Less allowance for estimated losses on loans/leases	(5,367,524)		(4,790,828)	(4,531,545)		(4,173,481)	(4,180,792)	(4,878,006)
Owner-occupied commercial real estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases	259,500,453			204,911,308
Commercial construction, land development, and other land [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases	49,585,072			44,962,381
Other commercial real estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases	405,615,528			344,105,550
Total Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases	714,701,053			593,979,239
Leases receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases	121,267,997			103,685,656
Plus deferred loan/lease origination costs	4,514,946			3,907,140
Total Loans/Leases plus deferred loan/lease origination costs	125,782,943			107,592,796
Less allowance for estimated losses on loans/leases	(2,323,509)		(2,187,605)	(1,990,395)		(1,884,985)	(1,610,999)	(1,339,496)
Loans/leases net of allowance for estimated losses	123,459,434			105,602,401
* Direct financing leases:
Net minimum lease payments to be received	136,848,442			117,719,380
Estimated unguaranteed residual values of leased assets	1,775,830			1,095,848
Unearned lease/residual income	(17,356,275)			(15,129,572)
Mortgage Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases	150,825,156	[1]		115,581,573	[1]
Loans Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases	77,226,363			76,720,514
Total [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases	1,535,277,543			1,284,211,234
Plus deferred loan/lease origination costs	4,106,282			3,176,405
Total Loans/Leases plus deferred loan/lease origination costs	1,539,383,825			1,287,387,639
Less allowance for estimated losses on loans/leases	$ (22,062,389)			$ (19,925,204)

[1] Includes residential real estate loans held for sale totaling $1,445,900 and $4,577,233 as of September 30, 2013, and December 31, 2012, respectively.