Note 4 - Loans and Allowance for Loan Losses (Details) - Age Analysis of Past Due Loans (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commercial:
Loans	$ 2,089,277,000	$ 1,053,243,000	$ 1,041,189,000
Originated Loan [Member] | Commercial and Industrial [Member]
Commercial:
Loans- 30 to 59 days past due	0	0
Loans- 60 to 89 days past due	0	0
Loans- Greater than 89 days past due	0	309,000
Loans- Total past due	0	309,000
Loans- Current	384,570,000	286,064,000
Loans	384,570,000	286,373,000
Loans- Recorded Balance >89days and accruing	0	0
Originated Loan [Member] | Commercial Vacant Land and Land Development and Residential Construction Loan [Member]
Commercial:
Loans- 30 to 59 days past due	0	0
Loans- 60 to 89 days past due	0	0
Loans- Greater than 89 days past due	0	0
Loans- Total past due	0	0
Loans- Current	29,826,000	36,741,000
Loans	29,826,000	36,741,000
Loans- Recorded Balance >89days and accruing	0	0
Originated Loan [Member] | Commercial Real Estate Owner Occupied Loan [Member]
Commercial:
Loans- 30 to 59 days past due	0	65,000
Loans- 60 to 89 days past due	0	0
Loans- Greater than 89 days past due	120,000	50,000
Loans- Total past due	120,000	115,000
Loans- Current	291,638,000	261,762,000
Loans	291,758,000	261,877,000
Loans- Recorded Balance >89days and accruing	0	0
Originated Loan [Member] | Commercial Real Estate Non Owner Occupied Loan [Member]
Commercial:
Loans- 30 to 59 days past due	0	0
Loans- 60 to 89 days past due	0	0
Loans- Greater than 89 days past due	116,000	0
Loans- Total past due	116,000	0
Loans- Current	410,861,000	364,066,000
Loans	410,977,000	364,066,000
Loans- Recorded Balance >89days and accruing	0	0
Originated Loan [Member] | Commercial Real Estate Multi Family and Residential Rental Loan [Member]
Commercial:
Loans- 30 to 59 days past due	0	0
Loans- 60 to 89 days past due	0	0
Loans- Greater than 89 days past due	0	64,000
Loans- Total past due	0	64,000
Loans- Current	36,058,000	37,575,000
Loans	36,058,000	37,639,000
Loans- Recorded Balance >89days and accruing	0	0
Originated Loan [Member] | Commercial Portfolio Segment [Member]
Commercial:
Loans- 30 to 59 days past due	0	65,000
Loans- 60 to 89 days past due	0	0
Loans- Greater than 89 days past due	236,000	423,000
Loans- Total past due	236,000	488,000
Loans- Current	1,152,953,000	986,208,000
Loans	1,153,189,000	986,696,000
Loans- Recorded Balance >89days and accruing	0	0
Originated Loan [Member] | Retail Home Equity and Other [Member]
Commercial:
Loans- 30 to 59 days past due	38,000	14,000
Loans- 60 to 89 days past due	3,000	0
Loans- Greater than 89 days past due	0	0
Loans- Total past due	41,000	14,000
Loans- Current	50,018,000	35,066,000
Loans	50,059,000	35,080,000
Loans- Recorded Balance >89days and accruing	0	0
Originated Loan [Member] | Retail 1-4 Family Mortgages [Member]
Commercial:
Loans- 30 to 59 days past due	0	21,000
Loans- 60 to 89 days past due	0	44,000
Loans- Greater than 89 days past due	366,000	375,000
Loans- Total past due	366,000	440,000
Loans- Current	42,502,000	31,027,000
Loans	42,868,000	31,467,000
Loans- Recorded Balance >89days and accruing	0	0
Originated Loan [Member] | Retail Loan [Member]
Commercial:
Loans- 30 to 59 days past due	38,000	35,000
Loans- 60 to 89 days past due	3,000	44,000
Loans- Greater than 89 days past due	366,000	375,000
Loans- Total past due	407,000	454,000
Loans- Current	92,520,000	66,093,000
Loans	92,927,000	66,547,000
Loans- Recorded Balance >89days and accruing	0	0
Originated Loan [Member]
Commercial:
Loans- 30 to 59 days past due	38,000	100,000
Loans- 60 to 89 days past due	3,000	44,000
Loans- Greater than 89 days past due	602,000	798,000
Loans- Total past due	643,000	942,000
Loans- Current	1,245,473,000	1,052,301,000
Loans	1,246,116,000	1,053,243,000
Loans- Recorded Balance >89days and accruing	0	0
Acquired Loan [Member] | Commercial and Industrial [Member]
Commercial:
Loans- 30 to 59 days past due	29,000
Loans- 60 to 89 days past due	32,000
Loans- Greater than 89 days past due	76,000
Loans- Total past due	137,000
Loans- Current	165,900,000
Loans	166,037,000	0
Loans- Recorded Balance >89days and accruing	0
Acquired Loan [Member] | Commercial Vacant Land and Land Development and Residential Construction Loan [Member]
Commercial:
Loans- 30 to 59 days past due	0
Loans- 60 to 89 days past due	38,000
Loans- Greater than 89 days past due	0
Loans- Total past due	38,000
Loans- Current	22,110,000
Loans	22,148,000	0
Loans- Recorded Balance >89days and accruing	0
Acquired Loan [Member] | Commercial Real Estate Owner Occupied Loan [Member]
Commercial:
Loans- 30 to 59 days past due	51,000
Loans- 60 to 89 days past due	425,000
Loans- Greater than 89 days past due	1,625,000
Loans- Total past due	2,101,000
Loans- Current	136,529,000
Loans	138,630,000	0
Loans- Recorded Balance >89days and accruing	0
Acquired Loan [Member] | Commercial Real Estate Non Owner Occupied Loan [Member]
Commercial:
Loans- 30 to 59 days past due	68,000
Loans- 60 to 89 days past due	598,000
Loans- Greater than 89 days past due	395,000
Loans- Total past due	1,061,000
Loans- Current	147,536,000
Loans	148,597,000	0
Loans- Recorded Balance >89days and accruing	0
Acquired Loan [Member] | Commercial Real Estate Multi Family and Residential Rental Loan [Member]
Commercial:
Loans- 30 to 59 days past due	37,000
Loans- 60 to 89 days past due	0
Loans- Greater than 89 days past due	105,000
Loans- Total past due	142,000
Loans- Current	86,560,000
Loans	86,702,000	0
Loans- Recorded Balance >89days and accruing	0
Acquired Loan [Member] | Commercial Portfolio Segment [Member]
Commercial:
Loans- 30 to 59 days past due	185,000
Loans- 60 to 89 days past due	1,093,000
Loans- Greater than 89 days past due	2,201,000
Loans- Total past due	3,479,000
Loans- Current	558,635,000
Loans	562,114,000	0
Loans- Recorded Balance >89days and accruing	0
Acquired Loan [Member] | Retail Home Equity and Other [Member]
Commercial:
Loans- 30 to 59 days past due	445,000
Loans- 60 to 89 days past due	419,000
Loans- Greater than 89 days past due	155,000
Loans- Total past due	1,019,000
Loans- Current	108,200,000
Loans	109,219,000	0
Loans- Recorded Balance >89days and accruing	26,000
Acquired Loan [Member] | Retail 1-4 Family Mortgages [Member]
Commercial:
Loans- 30 to 59 days past due	1,087,000
Loans- 60 to 89 days past due	408,000
Loans- Greater than 89 days past due	750,000
Loans- Total past due	2,245,000
Loans- Current	169,583,000
Loans	171,828,000	0
Loans- Recorded Balance >89days and accruing	0
Acquired Loan [Member] | Retail Loan [Member]
Commercial:
Loans- 30 to 59 days past due	1,532,000
Loans- 60 to 89 days past due	827,000
Loans- Greater than 89 days past due	905,000
Loans- Total past due	3,264,000
Loans- Current	277,783,000
Loans	281,047,000	0
Loans- Recorded Balance >89days and accruing	26,000
Acquired Loan [Member]
Commercial:
Loans- 30 to 59 days past due	1,717,000
Loans- 60 to 89 days past due	1,920,000
Loans- Greater than 89 days past due	3,106,000
Loans- Total past due	6,743,000
Loans- Current	836,418,000
Loans	843,161,000	0
Loans- Recorded Balance >89days and accruing	26,000
Commercial and Industrial [Member]
Commercial:
Loans	550,607,000	286,373,000
Commercial Vacant Land and Land Development and Residential Construction Loan [Member]
Commercial:
Loans	51,974,000	36,741,000
Commercial Real Estate Owner Occupied Loan [Member]
Commercial:
Loans	430,388,000	261,877,000
Commercial Real Estate Non Owner Occupied Loan [Member]
Commercial:
Loans	559,574,000	364,066,000
Commercial Real Estate Multi Family and Residential Rental Loan [Member]
Commercial:
Loans	122,760,000	37,639,000
Commercial Portfolio Segment [Member]
Commercial:
Loans	1,715,303,000	986,696,000	968,506,000
Retail Home Equity and Other [Member]
Commercial:
Loans	159,278,000	35,080,000
Retail 1-4 Family Mortgages [Member]
Commercial:
Loans	214,696,000	31,467,000
Retail Loan [Member]
Commercial:
Loans	$ 373,974,000	$ 66,547,000	$ 72,683,000