Consolidated Statements of Stockholders' Equity (Unaudited) (Parentheticals) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Cumulative Change in Accounting Principle, Tax		$ 1,109
Actuarially Determined Long-Term Liability Adjustments, Tax	$ 1,164	(1,214)
Interest Rate Hedge, Tax	144	933
Actuarially Determined Long-Term Liability Adjustments, Tax	$ (1,164)	$ 1,214

Amount of cumulative tax effect on beginning retained earnings from change in accounting principle.

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Amount of tax expense (benefit) for reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount, before reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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