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
	Mar. 31, 2021	Mar. 31, 2020
Earnings Per Share [Abstract]
Weighted average number of shares outstanding used to calculate basic EPS (in shares)	3,673	3,663
Dilutive securities:
Stock options and restricted share units (in shares)	262	245
Weighted average number of shares and share equivalents outstanding used to calculate diluted EPS (in shares)	3,935	3,908