Quarterly Results (Unaudited) - Summary of Unaudited Quarterly Results of Operations (Detail) - USD ($)	3 Months Ended								12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 185,443,000	$ 179,386,000	$ 177,426,000	$ 176,307,000	$ 171,359,000	$ 164,508,000	$ 157,743,000	$ 152,620,000	$ 718,562,000	$ 646,230,000	$ 552,644,000
Gross Profit	41,951,000	40,345,000	36,094,000	39,869,000	43,052,000	35,188,000	36,661,000	37,213,000	158,259,000	152,114,000	123,624,000
Net income	$ 18,169,000	$ 16,849,000	$ 14,656,000	$ 16,691,000	$ 19,637,000	$ 13,858,000	$ 16,072,000	$ 16,843,000	$ 66,365,000	$ 66,410,000	$ 46,356,000
Net Income per Basic Common Share	$ 1.06	$ 0.98	$ 0.84	$ 0.95	$ 1.11	$ 0.78	$ 0.90	$ 0.94	$ 3.83	$ 3.74	$ 2.59
Net Income per Diluted Common Share	$ 1.04	$ 0.96	$ 0.83	$ 0.94	$ 1.09	$ 0.76	$ 0.88	$ 0.92	$ 3.77	$ 3.66	$ 2.55