Note 9 - Non-pension Post-retirement Benefits - Amounts Recognized in Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Non-pension post-retirement benefits (current portion)	$ 3,817	$ 3,951
Non-pension post-retirement benefits	45,507	43,015
Non-Pension Post-retirement Benefit Plans [Member]
Non-pension post-retirement benefits (current portion)	3,817	3,951
Non-pension post-retirement benefits	45,507	43,015
Total non-pension post-retirement benefits liability	$ 49,324	$ 46,966

Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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