Unaudited: Quarterly Results of Operations, Common Stock Price and Dividends (Details) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2024 USD ($) Stockholder $ / shares	Sep. 30, 2024 USD ($) $ / shares	Jun. 30, 2024 USD ($) $ / shares	Mar. 31, 2024 USD ($) $ / shares	Dec. 31, 2023 USD ($) Stockholder $ / shares	Sep. 30, 2023 USD ($) $ / shares	Jun. 30, 2023 USD ($) $ / shares	Mar. 31, 2023 USD ($) $ / shares	Dec. 31, 2024 USD ($) Stockholder $ / shares	Dec. 31, 2023 USD ($) Stockholder $ / shares	Dec. 31, 2022 USD ($) $ / shares
Number of shareholders | Stockholder	562				562				562	562
Net sales | $	$ 205,182	$ 208,438	$ 216,658	$ 196,280	$ 182,440	$ 186,193	$ 175,858	$ 159,101	$ 826,558	$ 703,592	$ 565,568
Gross margin | $	82,760	83,878	85,368	77,178	71,465	72,723	69,434	62,816	329,184	276,438	219,970
Net Income (Loss) | $	$ 30,717	$ 32,038	$ 33,056	$ 29,131	$ 24,721	$ 25,969	$ 22,493	$ 19,415	$ 124,942	$ 92,598	$ 66,496
Earnings per share:
Basic	$ 1.05	$ 1.09	$ 1.13	$ 0.99	$ 0.84	$ 0.89	$ 0.77	$ 0.66	$ 4.26	$ 3.16	$ 2.28
Diluted	1.04	1.08	1.12	0.99	0.84	0.88	0.76	0.66	4.23	3.14	2.26
Dividends declared	0.34	0.34	0.27	0.27	0.27	0.27	0.23	0.23	1.22	0.99	$ 0.85
Stock price	212.12	218.41	186.35	161.81	154.37	143.87	147.56	121.82	212.12	154.37
High
Earnings per share:
Stock price	239.11	220.25	202.81	164.81	158.47	170.86	156.15	124.35	239.11	158.47
Low
Earnings per share:
Stock price	$ 193.00	$ 181.00	$ 151.18	$ 139.50	$ 134.06	$ 138.71	$ 117.53	$ 103.93	$ 193.00	$ 134.06