Note 3 - Loans and Allowance for Loan Losses (Details) - Components of Loan Portfolio - USD ($)	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 2,217,388,000	$ 2,089,277,000
Loans, percentage of portfolio	100.00%	100.00%
Loans, percentage of change in loans	6.10%
Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 1,519,710,000	$ 1,246,116,000	$ 1,186,713,000
Loans, percentage of portfolio	100.00%	100.00%
Loans, percentage of change in loans	22.00%
Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 697,678,000	$ 843,161,000
Loans, percentage of portfolio	100.00%	100.00%
Loans, percentage of change in loans	(17.30%)
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 1,877,620,000	$ 1,715,303,000
Loans, percentage of portfolio	84.70%	82.10%
Loans, percentage of change in loans	9.50%
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 643,118,000	$ 550,607,000
Loans, percentage of portfolio	29.00%	26.40%
Loans, percentage of change in loans	16.80%
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 47,734,000	$ 51,974,000
Loans, percentage of portfolio	2.20%	2.50%
Loans, percentage of change in loans	(8.20%)
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 427,016,000	$ 430,388,000
Loans, percentage of portfolio	19.30%	20.50%
Loans, percentage of change in loans	(0.80%)
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 636,227,000	$ 559,574,000
Loans, percentage of portfolio	28.60%	26.80%
Loans, percentage of change in loans	13.70%
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 123,525,000	$ 122,760,000
Loans, percentage of portfolio	5.60%	5.90%
Loans, percentage of change in loans	0.60%
Commercial Portfolio Segment [Member] | Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 1,402,320,000	$ 1,153,189,000	1,103,802,000
Loans, percentage of portfolio	92.30%	92.50%
Loans, percentage of change in loans	21.60%
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 522,346,000	$ 384,570,000
Loans, percentage of portfolio	34.40%	30.80%
Loans, percentage of change in loans	35.80%
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 30,958,000	$ 29,826,000
Loans, percentage of portfolio	2.00%	2.40%
Loans, percentage of change in loans	3.80%
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 306,539,000	$ 291,758,000
Loans, percentage of portfolio	20.20%	23.40%
Loans, percentage of change in loans	5.10%
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 505,715,000	$ 410,977,000
Loans, percentage of portfolio	33.30%	33.00%
Loans, percentage of change in loans	23.10%
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Retail Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 36,762,000	$ 36,058,000
Loans, percentage of portfolio	2.40%	2.90%
Loans, percentage of change in loans	2.00%
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 36,762,000	$ 36,058,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 475,300,000	$ 562,114,000
Loans, percentage of portfolio	68.10%	66.60%
Loans, percentage of change in loans	(15.40%)
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 120,772,000	$ 166,037,000
Loans, percentage of portfolio	17.30%	19.70%
Loans, percentage of change in loans	(27.30%)
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 16,776,000	$ 22,148,000
Loans, percentage of portfolio	2.40%	2.60%
Loans, percentage of change in loans	(24.30%)
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 120,477,000	$ 138,630,000
Loans, percentage of portfolio	17.30%	16.40%
Loans, percentage of change in loans	(13.10%)
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 130,512,000	$ 148,597,000
Loans, percentage of portfolio	18.70%	17.60%
Loans, percentage of change in loans	(12.20%)
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 86,763,000	$ 86,702,000
Loans, percentage of portfolio	12.40%	10.30%
Loans, percentage of change in loans	0.10%
Retail Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 339,768,000	$ 373,974,000
Loans, percentage of portfolio	15.30%	17.90%
Loans, percentage of change in loans	(9.10%)
Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 146,765,000	$ 159,278,000
Loans, percentage of portfolio	6.60%	7.60%
Loans, percentage of change in loans	(7.90%)
Retail Portfolio Segment [Member] | 1-4 Family Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 193,003,000	$ 214,696,000
Loans, percentage of portfolio	8.70%	10.30%
Loans, percentage of change in loans	(10.10%)
Retail Portfolio Segment [Member] | Originated Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 117,390,000	$ 92,927,000	$ 82,911,000
Loans, percentage of portfolio	7.70%	7.50%
Loans, percentage of change in loans	26.30%
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 65,671,000	$ 50,059,000
Loans, percentage of portfolio	4.30%	4.00%
Loans, percentage of change in loans	31.20%
Retail Portfolio Segment [Member] | Originated Loan [Member] | 1-4 Family Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 51,719,000	$ 42,868,000
Loans, percentage of portfolio	3.40%	3.50%
Loans, percentage of change in loans	20.60%
Retail Portfolio Segment [Member] | Acquired Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 222,378,000	$ 281,047,000
Loans, percentage of portfolio	31.90%	33.40%
Loans, percentage of change in loans	(20.90%)
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 81,094,000	$ 109,219,000
Loans, percentage of portfolio	11.60%	13.00%
Loans, percentage of change in loans	(25.80%)
Retail Portfolio Segment [Member] | Acquired Loan [Member] | 1-4 Family Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (in Dollars)	$ 141,284,000	$ 171,828,000
Loans, percentage of portfolio	20.30%	20.40%
Loans, percentage of change in loans	(17.80%)