SEGMENT REPORTING, Reportable Segment Information (Details) $ in Thousands	3 Months Ended
	Jun. 30, 2020 USD ($) Segment	Jun. 30, 2019 USD ($)	Mar. 31, 2020 USD ($)
SEGMENT REPORTING [Abstract]
Number of business segments | Segment	2
Reportable Segment Information [Abstract]
Net sales	$ 355,031	$ 381,372
Cost of Sales [Abstract]
Cost of sales	256,474	288,733
Gross profit	98,557	92,639
Selling, general, and administrative	69,467	65,787
Depreciation and amortization	3,516	3,463
Interest and financing costs	577	628
Operating expenses	73,560	69,878
Operating income	24,997	22,761
Other income (expense)	98	(45)
Earnings before tax	25,095	22,716
Net Sales [Abstract]
Contracts with customers	334,947	364,470
Financing and other	20,084	16,902
Net sales	355,031	381,372
Selected Financial Data - Statement of Cash Flow [Abstract]
Depreciation and amortization	4,779	4,964
Purchases of property, equipment and operating lease equipment	2,277	1,518
Selected Financial Data - Balance Sheet [Abstract]
Total assets	1,058,862	874,813	$ 909,113
Product [Member]
Reportable Segment Information [Abstract]
Net sales	307,240	335,601
Cost of Sales [Abstract]
Cost of sales	226,634	260,063
Net Sales [Abstract]
Net sales	307,240	335,601
Service [Member]
Reportable Segment Information [Abstract]
Net sales	47,791	45,771
Cost of Sales [Abstract]
Cost of sales	29,840	28,670
Net Sales [Abstract]
Net sales	47,791	45,771
Technology Segment [Member]
Reportable Segment Information [Abstract]
Net sales	341,224	368,535
Net Sales [Abstract]
Contracts with customers	333,987	363,681
Financing and other	7,237	4,854
Net sales	341,224	368,535
Operating Segments [Member] | Technology Segment [Member]
Reportable Segment Information [Abstract]
Net sales	341,224	368,535
Cost of Sales [Abstract]
Cost of sales	254,383	286,724
Gross profit	86,841	81,811
Selling, general, and administrative	65,556	62,667
Depreciation and amortization	3,488	3,407
Interest and financing costs	265	0
Operating expenses	69,309	66,074
Operating income	17,532	15,737
Net Sales [Abstract]
Contracts with customers	333,987	363,681
Financing and other	7,237	4,854
Net sales	341,224	368,535
Selected Financial Data - Statement of Cash Flow [Abstract]
Depreciation and amortization	3,634	1,339
Purchases of property, equipment and operating lease equipment	2,048	1,249
Selected Financial Data - Balance Sheet [Abstract]
Total assets	834,264	658,692
Operating Segments [Member] | Technology Segment [Member] | Product [Member]
Reportable Segment Information [Abstract]
Net sales	293,433	322,764
Cost of Sales [Abstract]
Cost of sales	224,543	258,054
Net Sales [Abstract]
Net sales	293,433	322,764
Operating Segments [Member] | Technology Segment [Member] | Service [Member]
Reportable Segment Information [Abstract]
Net sales	47,791	45,771
Cost of Sales [Abstract]
Cost of sales	29,840	28,670
Net Sales [Abstract]
Net sales	47,791	45,771
Operating Segments [Member] | Financing Segment [Member]
Reportable Segment Information [Abstract]
Net sales	13,807	12,837
Cost of Sales [Abstract]
Cost of sales	2,091	2,009
Gross profit	11,716	10,828
Selling, general, and administrative	3,911	3,120
Depreciation and amortization	28	56
Interest and financing costs	312	628
Operating expenses	4,251	3,804
Operating income	7,465	7,024
Net Sales [Abstract]
Contracts with customers	960	789
Financing and other	12,847	12,048
Net sales	13,807	12,837
Selected Financial Data - Statement of Cash Flow [Abstract]
Depreciation and amortization	1,145	3,625
Purchases of property, equipment and operating lease equipment	229	269
Selected Financial Data - Balance Sheet [Abstract]
Total assets	224,598	216,121
Operating Segments [Member] | Financing Segment [Member] | Product [Member]
Reportable Segment Information [Abstract]
Net sales	13,807	12,837
Cost of Sales [Abstract]
Cost of sales	2,091	2,009
Net Sales [Abstract]
Net sales	13,807	12,837
Operating Segments [Member] | Financing Segment [Member] | Service [Member]
Reportable Segment Information [Abstract]
Net sales	0	0
Cost of Sales [Abstract]
Cost of sales	0	0
Net Sales [Abstract]
Net sales	$ 0	$ 0