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Note 10 - Fair Value of Assets and Liabilities - Fair Value Measurements, Recorded (Details) - Fair Value, Recurring [Member] - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Assets:
Total assets at fair value	$ 59	$ 21
Liabilities:
Embedded customer derivative	59
Total liabilities recorded at fair value	3,851	21
Embedded customer derivatives		21
Total assets at fair value	59	21
Metal Swaps [Member]
Assets:
Metal swaps	59
Liabilities:
Fixed interest rate hedge		21
Interest Rate Swap [Member]
Liabilities:
Fixed interest rate hedge	3,792
Fair Value, Inputs, Level 1 [Member]
Assets:
Total assets at fair value
Liabilities:
Embedded customer derivative
Total liabilities recorded at fair value
Embedded customer derivatives
Total assets at fair value
Fair Value, Inputs, Level 1 [Member] \| Metal Swaps [Member]
Assets:
Metal swaps
Liabilities:
Fixed interest rate hedge
Fair Value, Inputs, Level 1 [Member] \| Interest Rate Swap [Member]
Liabilities:
Fixed interest rate hedge
Fair Value, Inputs, Level 2 [Member]
Assets:
Total assets at fair value	59	21
Liabilities:
Embedded customer derivative	59
Total liabilities recorded at fair value	3,851	21
Embedded customer derivatives		21
Total assets at fair value	59	21
Fair Value, Inputs, Level 2 [Member] \| Metal Swaps [Member]
Assets:
Metal swaps	59
Liabilities:
Fixed interest rate hedge		21
Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Liabilities:
Fixed interest rate hedge	3,792
Fair Value, Inputs, Level 3 [Member]
Assets:
Total assets at fair value
Liabilities:
Embedded customer derivative
Total liabilities recorded at fair value
Embedded customer derivatives
Total assets at fair value
Fair Value, Inputs, Level 3 [Member] \| Metal Swaps [Member]
Assets:
Metal swaps
Liabilities:
Fixed interest rate hedge
Fair Value, Inputs, Level 3 [Member] \| Interest Rate Swap [Member]
Liabilities:
Fixed interest rate hedge