Consolidated Statement of Stockholders' Equity (Parenthetical) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income tax benefit	$ 16,000	$ 16,000	$ 33,000	$ 33,000
Foreign currency hedging derivatives:
Tax benefit, hedge	0	(174,000)	0	186,000
Interest rate swaps:
Tax benefit, hedge	$ 0	$ (14,000)	$ 0	$ 164,000

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

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