Note 12 - Fair Value Measurements - Assets Measured at Fair Value Based on Significant Unobservable Inputs (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Beginning balance	$ 1,832	$ 243
Realized loss included in earnings - net mortgage banking derivatives	(21)	90
Purchases of available-for-sale securities		1,500
Principal redemption		(1)
Ending balance	1,811	1,832
Beginning balance	55	30
Realized loss included in earnings - net mortgage banking derivatives	16	25
Ending balance	71	55
Principal redemption		(1)
Equity Investment Other [Member]
Beginning balance	1,718	219
Realized loss included in earnings - net mortgage banking derivatives
Purchases of available-for-sale securities		1,500
Principal redemption		(1)
Ending balance	1,718	1,718
Beginning balance
Realized loss included in earnings - net mortgage banking derivatives
Ending balance
Principal redemption		(1)
Derivative Assets and Liabilities [Member]
Beginning balance	114	24
Realized loss included in earnings - net mortgage banking derivatives	(21)	90
Purchases of available-for-sale securities
Principal redemption
Ending balance	93	114
Beginning balance	55	30
Realized loss included in earnings - net mortgage banking derivatives	16	25
Ending balance	71	55
Principal redemption

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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