RECENT ACCOUNTING PRONOUNCEMENTS - Cumulative Effect of Adoption of Topic 606 on Statements Of Operations and Statements Of Comprehensive Income (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenues	$ 501,669	$ 226,534	$ 1,206,047	$ 640,760
Gross profit	215,137	114,125	477,609	325,040
Selling, general, and administrative	168,053	56,196	406,553	170,125
Total operating expenses	239,844	77,354	567,643	234,670
Operating income (loss)	(24,707)	36,771	(90,034)	90,370
Income (Loss) before income taxes	(49,614)	31,920	(142,555)	73,696
Income tax expense (benefit)	(7,880)	81,424	(28,583)	84,419
Net loss	$ (41,734)	$ (49,504)	$ (113,971)	$ (10,723)
Basic earnings (loss) per common share (in dollars per share)	$ (1.06)	$ (1.54)	$ (3.08)	$ (0.33)
Diluted earnings (loss) per common share (in dollars per share)	$ (1.06)	$ (1.54)	$ (3.08)	$ (0.33)
Comprehensive loss	$ (46,370)	$ (49,131)	$ (115,808)	$ (13,513)
Product [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenues	445,441	226,534	1,102,012	640,760
Service [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenues	56,228	$ 0	104,035	$ 0
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenues	498,711		1,200,588
Gross profit	212,179		472,150
Selling, general, and administrative	169,084		408,454
Total operating expenses	240,875		569,544
Operating income (loss)	(28,696)		(97,394)
Income (Loss) before income taxes	(53,603)		(149,915)
Income tax expense (benefit)	(8,596)		(29,856)
Net loss	$ (45,007)		$ (120,058)
Basic earnings (loss) per common share (in dollars per share)	$ (1.14)		$ (3.24)
Diluted earnings (loss) per common share (in dollars per share)	$ (1.14)		$ (3.24)
Comprehensive loss	$ (49,643)		$ (121,895)
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Product [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenues	442,397		1,096,386
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Service [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenues	56,314		104,202
Accounting Standards Update 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenues	(2,958)		(5,459)
Gross profit	(2,958)		(5,459)
Selling, general, and administrative	1,031		1,901
Total operating expenses	1,031		1,901
Operating income (loss)	(3,989)		(7,360)
Income (Loss) before income taxes	(3,989)		(7,360)
Income tax expense (benefit)	(716)		(1,273)
Net loss	$ (3,273)		$ (6,087)
Basic earnings (loss) per common share (in dollars per share)	$ (0.08)		$ (0.16)
Diluted earnings (loss) per common share (in dollars per share)	$ (0.08)		$ (0.16)
Comprehensive loss	$ (3,273)		$ (6,087)
Accounting Standards Update 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Product [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenues	(3,044)		(5,626)
Accounting Standards Update 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Service [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenues	$ 86		$ 167