CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2012
CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Sales of product and services	$ 1,013,374		$ 936,228		$ 784,951
Financing revenue	35,896		38,384		30,899
Fee and other income	8,266		8,500		9,731
TOTAL REVENUES	1,057,536		983,112		825,581
COSTS AND EXPENSES
Cost of sales, product and services	827,875		767,447		645,558
Direct lease costs	12,748		10,892		8,508
Total cost of sales	840,623		778,339		654,066
Professional and other fees	9,041		13,098		11,744
Salaries and benefits	123,151		110,963		98,268
General and administrative expenses	22,675		20,099		20,499
Interest and financing costs	1,948		1,868		1,430
Total expenses	156,815		146,028		131,941
TOTAL COSTS AND EXPENSES	997,438		924,367		786,007
EARNINGS BEFORE PROVISION FOR INCOME TAXES	60,098		58,745		39,574
PROVISION FOR INCOME TAXES	24,825		23,915		16,207
NET EARNINGS	$ 35,273		$ 34,830		$ 23,367
NET EARNINGS PER COMMON SHARE-BASIC (in dollars per share)	$ 4.41		$ 4.37	[1]	$ 2.82
NET EARNINGS PER COMMON SHARE-DILUTED (in dollars per share)	$ 4.37	[1]	$ 4.32	[1]	$ 2.79
WEIGHTED AVERAGE SHARES OUTSTANDING-BASIC (in shares)	7,927		7,810		8,002
WEIGHTED AVERAGE SHARES OUTSTANDING-DILUTED (in shares)	7,999		7,903		8,095

[1] Basic and diluted earnings per share are computed independently for each of the quarters presented. Therefore, the sum of quarterly basic and diluted per share information may not equal annual basic and diluted earnings per share.