Calculation of Earnings Per Share - Calculation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Earnings Per Share [Abstract]
Income (Loss) from Continuing Operations, Per Basic Share	$ 0.54	$ 0.71	$ 3.59	$ 3.46
Calculation of Basic Earnings Per Share:
Net Income	$ 9,662	$ 12,475	$ 63,646	$ 60,754
Weighted shares outstanding (shares)	17,737,984	17,582,115	17,715,845	17,538,461
Basic Earnings Per Share (in dollars per share)	$ 0.54	$ 0.71	$ 3.59	$ 3.46
Reconciliation of Numerator:
Net Income	$ 9,662	$ 12,475	$ 63,646	$ 60,754
Reconciliation of Denominator:
Weighted shares outstanding - Basic (shares)	17,737,984	17,582,115	17,715,845	17,538,461
Effect of dilutive securities:
Share-based compensation (shares)	81,389	77,528	81,156	71,697
Adjusted denominator-Diluted (shares)	17,819,373	17,659,643	17,797,001	17,610,158
Income (Loss) from Continuing Operations, Per Diluted Share	$ 0.54	$ 0.71	$ 3.58	$ 3.45
Diluted Earnings Per Share (in dollars per share)	$ 0.54	$ 0.71	$ 3.58	$ 3.45
Net Income	$ 9,662	$ 12,475	$ 63,646	$ 60,754
Basic (shares)	17,737,984	17,582,115	17,715,845	17,538,461
Income (Loss) from Continuing Operations, Per Basic Share	$ 0.54	$ 0.71	$ 3.59	$ 3.46
Basic (in dollars per share)	$ 0.54	$ 0.71	$ 3.59	$ 3.46
Share-based compensation (shares)	81,389	77,528	81,156	71,697
Diluted (shares)	17,819,373	17,659,643	17,797,001	17,610,158
Income (Loss) from Continuing Operations, Per Diluted Share	$ 0.54	$ 0.71	$ 3.58	$ 3.45
Diluted (in dollars per share)	$ 0.54	$ 0.71	$ 3.58	$ 3.45
Retained Earnings [Member]
Earnings Per Share [Abstract]
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	$ 9,662	$ 12,475	$ 63,646	$ 60,754
Calculation of Basic Earnings Per Share:
Net Income	9,662	12,475	63,646	60,754
Reconciliation of Numerator:
Net Income	9,662	12,475	63,646	60,754
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	9,662	12,475	63,646	60,754
Net Income	$ 9,662	$ 12,475	$ 63,646	$ 60,754