Note 4 - Loans and Allowance for Loan Losses (Details) - Components of Loan Portfolio (USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 2,120,760,000	$ 2,089,277,000
Loans, percentage of portfolio	100.00%	100.00%
Loans, percentage of change in loans	1.50%
Commercial and Industrial [Member] | Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	434,211,000	384,570,000
Loans, percentage of portfolio	32.60%	30.80%
Loans, percentage of change in loans	12.90%
Commercial and Industrial [Member] | Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	153,464,000	166,037,000
Loans, percentage of portfolio	19.40%	19.70%
Loans, percentage of change in loans	(7.60%)
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	587,675,000	550,607,000
Loans, percentage of portfolio	27.70%	26.40%
Loans, percentage of change in loans	6.70%
Vacant Land and Land Development and Residential Construction Loan [Member] | Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	35,948,000	29,826,000
Loans, percentage of portfolio	2.70%	2.40%
Loans, percentage of change in loans	20.50%
Vacant Land and Land Development and Residential Construction Loan [Member] | Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	20,102,000	22,148,000
Loans, percentage of portfolio	2.50%	2.60%
Loans, percentage of change in loans	(9.20%)
Vacant Land and Land Development and Residential Construction Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	56,050,000	51,974,000
Loans, percentage of portfolio	2.70%	2.50%
Loans, percentage of change in loans	7.80%
Real Estate Owner Occupied Loan [Member] | Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	302,379,000	291,758,000
Loans, percentage of portfolio	22.80%	23.40%
Loans, percentage of change in loans	3.60%
Real Estate Owner Occupied Loan [Member] | Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	129,616,000	138,630,000
Loans, percentage of portfolio	16.40%	16.40%
Loans, percentage of change in loans	(6.50%)
Real Estate Owner Occupied Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	431,995,000	430,388,000
Loans, percentage of portfolio	20.40%	20.50%
Loans, percentage of change in loans	0.40%
Real Estate Non Owner Occupied Loan [Member] | Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	423,381,000	410,977,000
Loans, percentage of portfolio	31.90%	33.00%
Loans, percentage of change in loans	3.00%
Real Estate Non Owner Occupied Loan [Member] | Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	142,771,000	148,597,000
Loans, percentage of portfolio	18.00%	17.60%
Loans, percentage of change in loans	(3.90%)
Real Estate Non Owner Occupied Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	566,152,000	559,574,000
Loans, percentage of portfolio	26.70%	26.80%
Loans, percentage of change in loans	1.20%
Real Estate Multi Family and Residential Rental Loan [Member] | Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	34,922,000	36,058,000
Loans, percentage of portfolio	2.60%	2.90%
Loans, percentage of change in loans	(3.20%)
Real Estate Multi Family and Residential Rental Loan [Member] | Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	82,555,000	86,702,000
Loans, percentage of portfolio	10.40%	10.30%
Loans, percentage of change in loans	(4.80%)
Real Estate Multi Family and Residential Rental Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	117,477,000	122,760,000
Loans, percentage of portfolio	5.50%	5.90%
Loans, percentage of change in loans	(4.30%)
Home Equity and Other [Member] | Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	53,707,000	50,059,000
Loans, percentage of portfolio	4.10%	4.00%
Loans, percentage of change in loans	7.30%
Home Equity and Other [Member] | Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	99,279,000	109,219,000
Loans, percentage of portfolio	12.50%	13.00%
Loans, percentage of change in loans	(9.10%)
Home Equity and Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	152,986,000	159,278,000
Loans, percentage of portfolio	7.20%	7.60%
Loans, percentage of change in loans	(4.00%)
1-4 Family Mortgages [Member] | Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	44,165,000	42,868,000
Loans, percentage of portfolio	3.30%	3.50%
Loans, percentage of change in loans	3.00%
1-4 Family Mortgages [Member] | Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	164,260,000	171,828,000
Loans, percentage of portfolio	20.80%	20.40%
Loans, percentage of change in loans	(4.40%)
1-4 Family Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	208,425,000	214,696,000
Loans, percentage of portfolio	9.80%	10.30%
Loans, percentage of change in loans	(2.90%)
Retail Loan [Member] | Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	97,872,000	92,927,000
Loans, percentage of portfolio	7.40%	7.50%
Loans, percentage of change in loans	5.30%
Retail Loan [Member] | Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	263,539,000	281,047,000
Loans, percentage of portfolio	33.30%	33.40%
Loans, percentage of change in loans	(6.20%)
Retail Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	361,411,000	373,974,000
Loans, percentage of portfolio	17.00%	17.90%
Loans, percentage of change in loans	(3.40%)
Commercial Portfolio Segment [Member] | Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	1,230,841,000	1,153,189,000	1,004,218,000
Loans, percentage of portfolio	92.60%	92.50%
Loans, percentage of change in loans	6.70%
Commercial Portfolio Segment [Member] | Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	528,508,000	562,114,000
Loans, percentage of portfolio	66.70%	66.60%
Loans, percentage of change in loans	(6.00%)
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	1,759,349,000	1,715,303,000
Loans, percentage of portfolio	83.00%	82.10%
Loans, percentage of change in loans	2.60%
Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	1,328,713,000	1,246,116,000	1,066,796,000
Loans, percentage of portfolio	100.00%	100.00%
Loans, percentage of change in loans	6.60%
Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 792,047,000	$ 843,161,000
Loans, percentage of portfolio	100.00%	100.00%
Loans, percentage of change in loans	(6.10%)