SEGMENT REPORTING (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Segment Reporting Information [Line Items]
Sales of product and services									$ 936,228	$ 784,951	$ 672,303
Financing revenues									38,384	30,899	35,367
Fee and other income									8,500	9,731	10,720
Patent settlement income									0	0	125
Total revenues	236,312	242,025	260,051	244,724	218,999	224,028	203,655	178,899	983,112	825,581	718,515
Cost of sales, product and services									767,447	645,558	551,860
Direct lease costs									10,892	8,508	9,212
Professional and other fees									13,098	11,744	15,383
Salaries and benefits									110,963	98,268	84,247
General and administrative expenses									20,099	20,499	14,681
Interest and financing costs									1,868	1,430	2,564
Earnings before provision for income taxes	12,745	15,529	16,908	13,563	7,009	14,434	11,848	6,283	58,745	39,574	40,568
Assets	437,872				433,688				437,872	433,688	389,191
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									983,112	825,581	718,515
Assets	437,872				433,688				437,872	433,688
U.S.
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									964,996	812,364	714,736
Assets	435,486				431,632				435,486	431,632
Non U.S [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									18,116	13,217	3,779
Assets	2,386				2,056				2,386	2,056
Technology [Member]
Segment Reporting Information [Line Items]
Sales of product and services									936,228	784,951	672,303
Financing revenues									0	0	0
Fee and other income									6,949	7,455	8,260
Patent settlement income									0	0	125
Total revenues									943,177	792,406	680,688
Cost of sales, product and services									767,447	645,558	551,860
Direct lease costs									0	0	0
Professional and other fees									9,638	10,283	14,014
Salaries and benefits									100,447	88,321	74,706
General and administrative expenses									19,028	16,627	13,220
Interest and financing costs									89	93	84
Earnings before provision for income taxes									46,528	31,524	26,804
Assets	255,257				241,488				255,257	241,488	206,963
Financing [Member]
Segment Reporting Information [Line Items]
Sales of product and services									0	0	0
Financing revenues									38,384	30,899	35,367
Fee and other income									1,551	2,276	2,460
Patent settlement income									0	0	0
Total revenues									39,935	33,175	37,827
Cost of sales, product and services									0	0	0
Direct lease costs									10,892	8,508	9,212
Professional and other fees									3,460	1,461	1,369
Salaries and benefits									10,516	9,947	9,541
General and administrative expenses									1,071	3,872	1,461
Interest and financing costs									1,779	1,337	2,480
Earnings before provision for income taxes									12,217	8,050	13,764
Assets	$ 182,615				$ 192,200				$ 182,615	$ 192,200	$ 182,228