Stock-Based Compensation (Summary Of Stock Options And Warrants) (Details) (USD $)	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Option Shares Reserved [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Beginning	155,230	158,230	162,230
Granted	(4,000)	(4,000)	(4,000)
Terminated		(1,000)
Options Outstanding, Ending	151,230	155,230	158,230
Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Beginning	38,000	49,000	109,000
Granted	4,000	4,000	4,000
Exercised	(6,910)	(14,000)	(64,000)
Terminated		(1,000)
Options Outstanding, Ending	35,090	38,000	49,000
Weighted Average Option Exercise Price, Beginning	31.78	30.27	25.85
Granted	67.69	49.86	54.11
Exercised	43.81	29.77	24.23
Terminated		58.27
Weighted Average Option Exercise Price, Ending	33.51	31.78	30.27
Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Beginning	2,000	4,000	10,000
Terminated	(2,000)	(2,000)	(6,000)
Options Outstanding, Ending		2,000	4,000
Weighted Average Option Exercise Price, Beginning	37.38	29.69	16.28
Terminated	37.38	21.99	7.35
Weighted Average Option Exercise Price, Ending		37.38	29.69