Note 9 - Borrowings (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Proceeds from (Payments for) in Securities Sold under Agreements to Repurchase	$ (25,670)	$ (971)
Long-term Debt, Total	0
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	856,760
Unsecured Line of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 15,000
Debt Instrument, Basis Spread on Variable Rate	2.00%
Long-term Line of Credit, Total	$ 0		$ 0
Federal Home Loan Bank Borrowings [Member]
Debt Instrument, Unused Borrowing Capacity, Amount	397,660
Deposit Liabilities, Collateral Issued, Financial Instruments	144,380
Wholesale Repurchase Agreements [Member]
Proceeds from (Payments for) in Securities Sold under Agreements to Repurchase	$ (25,000)

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash flow from investments sold under the agreement to repurchase such investment.

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