BALANCE SHEET ITEMS - Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended
Dec. 31, 2020	Mar. 31, 2020
Activity in goodwill account
Balance at April 1, 2020	$ 1,065,000
Foreign currency translation adjustments	44,000
Balance at December 31, 2020	1,109,000
Gross Carrying Amount	538,000	$ 520,000
Accumulated Amortization	(305,000)	(258,000)
Total amortization expense	233,000	262,000
Customer-related intangibles
Activity in goodwill account
Gross Carrying Amount	280,000	275,000
Accumulated Amortization	(149,000)	(128,000)
Total amortization expense	131,000	147,000
Licenses and other intangibles
Activity in goodwill account
Gross Carrying Amount	258,000	245,000
Accumulated Amortization	(156,000)	(130,000)
Total amortization expense	102,000	$ 115,000
FAS \| Communications, Enterprise and Cloud
Activity in goodwill account
Balance at April 1, 2020	188,000
Foreign currency translation adjustments	1,000
Balance at December 31, 2020	189,000
FAS \| Lifestyle
Activity in goodwill account
Balance at April 1, 2020	131,000
Foreign currency translation adjustments	0
Balance at December 31, 2020	131,000
FAS \| Consumer Devices
Activity in goodwill account
Balance at April 1, 2020	51,000
Foreign currency translation adjustments	0
Balance at December 31, 2020	51,000
FRS \| Automotive
Activity in goodwill account
Balance at April 1, 2020	174,000
Foreign currency translation adjustments	39,000
Balance at December 31, 2020	213,000
FRS \| Health Solutions
Activity in goodwill account
Balance at April 1, 2020	192,000
Foreign currency translation adjustments	4,000
Balance at December 31, 2020	196,000
FRS \| Industrial
Activity in goodwill account
Balance at April 1, 2020	329,000
Foreign currency translation adjustments	0
Balance at December 31, 2020	$ 329,000

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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