CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Other comprehensive income
Adjustments related to retirement plans, tax expense	$ 16	$ 10	$ 48	$ 30

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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+ Details