Shareholders' Equity - Summary of Activity Related to Common Shares Outstanding (Detail) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Equity [Abstract]
Common stock shares outstanding, Beginning balance	18,429,350	18,611,289
Issuance of common stock on exercise of stock options	2,420	19,606
Restricted stock awards, net of cancellations	171,634	202,748
Director share awards	61,186	60,998
Equity awards under Short-Term Incentive Plan	0	189,121
Issuance of common stock from purchase of Employee Stock Purchase Plan shares	164,258	157,706
Cancellation of stock for withholding tax for vested shares	(95,674)	(148,499)
Common stock Repurchases	(495,144)	(663,619)
Common stock shares outstanding, End of Year	18,238,030	18,429,350