Note 11 - Fair Value Measurements (Details) - Fair Values of Financial Instruments (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
Assets
Carrying Value-Cash and due from banks	$ 7,920,000	$ 9,577,000	$ 8,013,000
Fair Value-Cash and due from banks	7,920,000	9,577,000
Carrying Value Federal funds sold	8,968,000	5,695,000	3,844,000
Fair Value Federal funds sold	8,968,000	5,695,000	3,844,000
Carrying Value Interest bearing deposits with other banks	191,468,000	291,688,000	208,522,000
Fair Value Interest bearing deposits with other banks	191,468,000	291,688,000	208,522,000
Carrying Value Investment securities	382,468,000	378,133,000	355,830,000
Fair Value Investment securities	382,468,000	378,133,000	355,830,000
Carrying Value Federal Reserve and Federal Home Loan Bank stock	10,657,000	11,272,000
Fair Value Federal Reserve and Federal Home Loan Bank stock	10,657,000	11,272,000
Carrying Value Loans held for sale	41,254,000	42,030,000	39,206,000
Fair Value Loans held for sale	41,254,000	42,030,000
Carrying Value Loans	3,432,548,000	2,945,158,000	2,796,840,000
Fair Value Loans	3,458,861,000	2,979,180,000
Carrying Value Bank owned life insurance	40,432,000	39,738,000	29,555,000
Fair Value Bank owned life insurance	40,432,000	39,738,000	29,555,000
Carrying Value Annuity investment	11,235,000	11,227,000
Fair Value Annuity investment	11,235,000	11,227,000
Derivative assets	34,000		0
Derivative assets	34,000		0
Liabilities
Carrying Value Noninterest bearing deposits	3,533,850,000	3,225,414,000	2,984,059,000
Carrying Value Borrowings	168,257,000	119,771,000
Fair Value Borrowings	169,680,000	120,764,000
Derivative liabilites	18,000		0
Derivative liabilites	18,000		0
Fair Value, Inputs, Level 1 [Member]
Assets
Carrying Value Investment securities	180,000	165,000
Fair Value Investment securities	180,000	165,000
Fair Value, Inputs, Level 2 [Member] \| Noninterest-bearing Deposits [Member]
Liabilities
Fair Value Noninterest bearing deposits	1,056,559,000	849,409,000
Fair Value, Inputs, Level 2 [Member] \| Interest-bearing Deposits [Member]
Liabilities
Fair Value Noninterest bearing deposits	2,476,632,000	2,375,861,000
Fair Value, Inputs, Level 2 [Member]
Assets
Fair Value-Cash and due from banks	7,920,000	9,577,000
Carrying Value Federal funds sold	8,968,000	5,695,000
Fair Value Federal funds sold	8,968,000	5,695,000
Carrying Value Interest bearing deposits with other banks	191,468,000	291,688,000
Fair Value Interest bearing deposits with other banks	191,468,000	291,688,000
Carrying Value Investment securities	382,069,000	377,749,000
Fair Value Investment securities	382,069,000	377,749,000
Fair Value Federal Reserve and Federal Home Loan Bank stock	10,657,000	11,272,000
Fair Value Loans held for sale	41,254,000	42,030,000
Fair Value Loans	7,380,000	14,249,000
Carrying Value Bank owned life insurance	40,432,000	39,738,000
Fair Value Bank owned life insurance	40,432,000	39,738,000
Carrying Value Annuity investment	11,235,000	11,227,000
Fair Value Annuity investment	11,235,000	11,227,000
Liabilities
Fair Value Borrowings	165,373,000	120,764,000
Fair Value, Inputs, Level 3 [Member]
Assets
Carrying Value Investment securities	219,000	219,000
Fair Value Investment securities	219,000	219,000
Fair Value Loans	3,451,481,000	2,964,931,000
Derivative assets	34,000
Derivative assets	34,000
Liabilities
Derivative liabilites	18,000
Derivative liabilites	18,000
Noninterest-bearing Deposits [Member]
Liabilities
Carrying Value Noninterest bearing deposits	1,056,559,000	849,409,000
Fair Value Noninterest bearing deposits	1,056,559,000	849,409,000
Interest-bearing Deposits [Member]
Liabilities
Carrying Value Noninterest bearing deposits	2,477,291,000	2,376,005,000
Fair Value Noninterest bearing deposits	$ 2,476,632,000	$ 2,375,861,000

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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The amount outstanding of funds lent to other depository institutions, securities brokers, or securities dealers in the form of Federal Funds sold; for example, immediately available funds lent under agreements or contracts that mature in one business day or roll over under a continuing contract, regardless of the nature of the transaction or the collateral involved, excluding overnight lending for commercial and industrial purposes. Also include Federal Funds sold under agreements to resell on a gross basis, excluding (1) sales of term Federal Funds, (2) due bills representing purchases of securities or other assets by the reporting bank that have not yet been delivered and similar instruments, (3) resale agreements that mature in more than one business day involving assets other than securities, and (4) yield maintenance dollar repurchase agreements.

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Amount classified as loans attributable to disposal group held for sale or disposed of. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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Fair value portion of other liabilities.

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