Note 7 - Fair Value of Financial Instruments - Fair Value Measurements, Recorded (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Derivative assets	$ 70	$ 113
Embedded customer derivative	40	113
Total liabilities recorded at fair value	52	149
Metal Swaps [Member]
Derivative assets	70
Derivative liabilities		113
Interest Rate Swap [Member]
Derivative liabilities	12	36
Fair Value, Inputs, Level 1 [Member]
Derivative assets
Embedded customer derivative
Total liabilities recorded at fair value
Fair Value, Inputs, Level 1 [Member] \| Metal Swaps [Member]
Derivative assets
Derivative liabilities
Fair Value, Inputs, Level 1 [Member] \| Interest Rate Swap [Member]
Derivative liabilities
Fair Value, Inputs, Level 2 [Member]
Derivative assets	70	113
Embedded customer derivative	40	113
Total liabilities recorded at fair value	52	149
Fair Value, Inputs, Level 2 [Member] \| Metal Swaps [Member]
Derivative assets	70
Derivative liabilities		113
Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Derivative liabilities	12	36
Fair Value, Inputs, Level 3 [Member]
Derivative assets
Embedded customer derivative
Total liabilities recorded at fair value
Fair Value, Inputs, Level 3 [Member] \| Metal Swaps [Member]
Derivative assets
Derivative liabilities
Fair Value, Inputs, Level 3 [Member] \| Interest Rate Swap [Member]
Derivative liabilities

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226008-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13495-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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- Definition

Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as an asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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