UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Net sales	$ 298,644	$ 306,241	$ 904,796	$ 876,017
Cost of sales	234,584	240,803	709,685	690,216
Gross profit	64,060	65,438	195,111	185,801
Professional and other fees	1,882	1,436	4,913	4,846
Salaries and benefits	37,372	35,632	108,326	102,831
General and administrative expenses	6,765	7,233	21,129	20,664
Interest and financing costs	396	575	1,371	1,830
Operating expenses	46,415	44,876	135,739	130,171
Operating income	17,645	20,562	59,372	55,630
Other income	0	6,169	0	7,603
Earnings before tax	17,645	26,731	59,372	63,233
Provision for income taxes	7,348	11,230	24,582	26,303
Net earnings	$ 10,297	$ 15,501	$ 34,790	$ 36,930
Net earnings per common share-basic (In dollars per share)	$ 1.41	$ 2.14	$ 4.79	$ 5.02
Net earnings per common share-diluted (In dollars per share)	$ 1.40	$ 2.13	$ 4.74	$ 4.97
Weighted average common shares outstanding-basic (In shares)	7,280	7,230	7,260	7,351
Weighted average common shares outstanding-diluted (In shares)	7,329	7,279	7,336	7,413