Note 6 - Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Amortized cost	$ 313,907	$ 181,229
Gross unrealized gains	708	427
Gross unrealized losses	5,099	2,508
Fair value	309,516	179,148
US Government Agencies Debt Securities [Member]
Amortized cost	17,529	9,008
Gross unrealized gains	54	13
Gross unrealized losses	144	68
Fair value	17,439	8,953
Corporate Debt Securities [Member]
Amortized cost	13,052	13,074
Gross unrealized gains	76	59
Gross unrealized losses	436	92
Fair value	12,692	13,041
Collateralized Mortgage Backed Securities [Member]
Amortized cost	168,854	81,763
Gross unrealized gains	328	2
Gross unrealized losses	3,564	1,824
Fair value	165,618	79,941
US States and Political Subdivisions Debt Securities [Member]
Amortized cost	114,472	76,553
Gross unrealized gains	250	353
Gross unrealized losses	955	427
Fair value	113,767	76,479
Other Debt Obligations [Member]
Amortized cost		831
Gross unrealized gains	0	0
Gross unrealized losses		97
Fair value		$ 734

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

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

+ Details

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

+ Details

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

+ Details

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- Details

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- Details

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