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		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share [Abstract]
Weighted average number of shares outstanding used to calculate basic EPS (in shares)	3,623	3,682	3,648	3,673
Dilutive securities:
Stock options and restricted share units (in shares)	274	179	269	208
Weighted average number of shares and share equivalents outstanding used to calculate diluted EPS (in shares)	3,897	3,861	3,917	3,881