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

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Fair value of financial and nonfinancial obligations.

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Note 7 - Fair Value of Financial Instruments - Fair Value Measurements, Recorded (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Derivative assets	$ 278	$ 382
Liabilities:
Embedded customer derivatives	278	382
Total liabilities recorded at fair value	278	387
Assets:
Derivative assets	278	382
Metal Swaps [Member]
Derivative assets	278
Liabilities:
Derivative liabilities		382
Assets:
Derivative liabilities		382
Derivative assets	278
Interest Rate Swap [Member]
Liabilities:
Derivative liabilities		5
Assets:
Derivative liabilities		5
Fair Value, Inputs, Level 1 [Member]
Derivative assets
Liabilities:
Embedded customer derivatives
Total liabilities recorded at fair value
Assets:
Derivative assets
Fair Value, Inputs, Level 1 [Member] \| Metal Swaps [Member]
Derivative assets
Liabilities:
Derivative liabilities
Assets:
Derivative liabilities
Derivative assets
Fair Value, Inputs, Level 1 [Member] \| Interest Rate Swap [Member]
Liabilities:
Derivative liabilities
Assets:
Derivative liabilities
Fair Value, Inputs, Level 2 [Member]
Derivative assets	278	382
Liabilities:
Embedded customer derivatives	278	382
Total liabilities recorded at fair value	278	387
Assets:
Derivative assets	278	382
Fair Value, Inputs, Level 2 [Member] \| Metal Swaps [Member]
Derivative assets	278
Liabilities:
Derivative liabilities		382
Assets:
Derivative liabilities		382
Derivative assets	278
Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Liabilities:
Derivative liabilities		5
Assets:
Derivative liabilities		5
Fair Value, Inputs, Level 3 [Member]
Derivative assets
Liabilities:
Embedded customer derivatives
Total liabilities recorded at fair value
Assets:
Derivative assets
Fair Value, Inputs, Level 3 [Member] \| Metal Swaps [Member]
Derivative assets
Liabilities:
Derivative liabilities
Assets:
Derivative liabilities
Derivative assets
Fair Value, Inputs, Level 3 [Member] \| Interest Rate Swap [Member]
Liabilities:
Derivative liabilities
Assets:
Derivative liabilities