Earnings Per Share - Weighted Average Shares and Share Equivalents Used to Calculate Basic and Diluted Earnings Per Share (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Earnings Per Share [Abstract]
Weighted average number of shares outstanding used to calculate basic EPS (in shares)	3,258,863	3,265,914	3,253,623	3,312,145
Dilutive securities:
Stock options and restricted share units (in shares)	199,279	205,473	201,477	231,559
Weighted average number of shares and share equivalents outstanding used to calculate diluted EPS (in shares)	3,458,142	3,471,387	3,455,100	3,543,704