Note 11 - Fair Value of Assets and Liabilities - Fair Value Measurements, Recorded (Details) - Fair Value, Recurring [Member] - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets:
Embedded customer derivatives	$ 4	$ 21
Total assets at fair value	4	21
Liabilities:
Total liabilities recorded at fair value	3,046	21
Embedded customer derivatives	4	21
Total assets at fair value	4	21
Metal Swaps [Member]
Liabilities:
Derivative Liability, Total	4	21
Interest Rate Swap [Member]
Liabilities:
Derivative Liability, Total	3,042
Fair Value, Inputs, Level 1 [Member]
Assets:
Embedded customer derivatives
Total assets at fair value
Liabilities:
Total liabilities recorded at fair value
Embedded customer derivatives
Total assets at fair value
Fair Value, Inputs, Level 1 [Member] | Metal Swaps [Member]
Liabilities:
Derivative Liability, Total
Fair Value, Inputs, Level 1 [Member] | Interest Rate Swap [Member]
Liabilities:
Derivative Liability, Total
Fair Value, Inputs, Level 2 [Member]
Assets:
Embedded customer derivatives	4	21
Total assets at fair value	4	21
Liabilities:
Total liabilities recorded at fair value	3,046	21
Embedded customer derivatives	4	21
Total assets at fair value	4	21
Fair Value, Inputs, Level 2 [Member] | Metal Swaps [Member]
Liabilities:
Derivative Liability, Total	4	21
Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member]
Liabilities:
Derivative Liability, Total	3,042
Fair Value, Inputs, Level 3 [Member]
Assets:
Embedded customer derivatives
Total assets at fair value
Liabilities:
Total liabilities recorded at fair value
Embedded customer derivatives
Total assets at fair value
Fair Value, Inputs, Level 3 [Member] | Metal Swaps [Member]
Liabilities:
Derivative Liability, Total
Fair Value, Inputs, Level 3 [Member] | Interest Rate Swap [Member]
Liabilities:
Derivative Liability, Total