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Consolidated Statements of Shareholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Stockholders' Equity [Abstract]
Minimum pension and post retirement benefit plan adjustments, net of taxes	$ 116	$ 24	$ 225

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