Consolidated Statements of Shareholders' Equity (Parenthetical) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares
Statement Of Stockholders Equity [Abstract]
Tax effect on employee benefit funded status adjustment | $	$ 112	$ 69	$ 16
Cash dividends (in dollars per share)	$ 0.76	$ 0.70	$ 0.64
Issuance of treasury stock (in shares) | shares	19	22	72
Common stock, par value (in dollars per share)	$ 1	$ 1	$ 1