Note 12 - Income Taxes (Details) - Gross Deferred Tax Assets and Liabilities (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets
Allowance for credit losses	$ 18,544	$ 16,440	$ 15,035
Deferred loan fees and costs	10,337	5,039	3,020
Stock-based compensation	1,714	1,370	829
Net operating loss	3,198	3,449	3,952
Unrealized loss on securities available for sale		2,213
SERP	1,421
Premises and equipment	1,590	1,283	989
Other	71us-gaap_DeferredTaxAssetsOther	4us-gaap_DeferredTaxAssetsOther	4us-gaap_DeferredTaxAssetsOther
Total deferred tax assets	36,875us-gaap_DeferredTaxAssetsGross	29,798us-gaap_DeferredTaxAssetsGross	23,829us-gaap_DeferredTaxAssetsGross
Deferred tax liabilities
Unrealized gain on securities available for sale	(1,765)		(3,643)
Excess servicing	(114)	(95)	(58)
Deferred rent	(162)us-gaap_DeferredRentCredit	(264)us-gaap_DeferredRentCredit	(322)us-gaap_DeferredRentCredit
Intangible assets	(2,323)	(490)	(678)
Total deferred tax liabilities	(4,364)us-gaap_DeferredIncomeTaxLiabilities	(849)us-gaap_DeferredIncomeTaxLiabilities	(4,701)us-gaap_DeferredIncomeTaxLiabilities
Net deferred income tax amount	$ 32,511us-gaap_DeferredTaxAssetsDeferredIncome	$ 28,949us-gaap_DeferredTaxAssetsDeferredIncome	$ 19,128us-gaap_DeferredTaxAssetsDeferredIncome

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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