Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Sales	$ 104,568	$ 104,993	$ 260,273	$ 259,342
Costs and expenses
Cost of sales	69,380	68,670	174,852	173,023
Selling, general and administrative expenses	19,967	21,102	57,367	57,754
Interest expense (income), net	39	43	(43)	39
Other (income) expense, net	(9)	36	(9)	(43)
Total costs and expenses	89,377	89,851	232,167	230,773
Income before income taxes	15,191	15,142	28,106	28,569
Income tax expense	5,527	5,374	10,281	10,279
Net income	$ 9,664	$ 9,768	$ 17,825	$ 18,290
Net income per common share:
Basic (in dollars per share)	$ 1.07	$ 1.05	$ 1.94	$ 1.96
Diluted (in dollars per share)	$ 1.06	$ 1.04	$ 1.92	$ 1.95
Weighted average shares outstanding:
Basic (in shares)	9,037	9,331	9,175	9,321
Diluted (in shares)	9,126	9,420	9,271	9,403
Cash dividends per share of common stock (in dollars per share)	$ 0.18	$ 0.15	$ 0.54	$ 0.45