Earnings Per Share - Weighted Average Shares and Share Equivalents Used to Calculate Basic and Diluted Earnings Per Share (Detail) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Weighted average number of shares outstanding used to calculate basic EPS (in shares)	3,706	3,672	3,684	3,631
Dilutive securities:
Stock options and restricted share units (in shares)	233	316	212	343
Weighted average number of shares and share equivalents outstanding used to calculate diluted EPS (in shares)	3,939	3,988	3,896	3,974