Cash, Cash Equivalents, Short-term and Long-term Investments, Amortized Cost

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Cash, Cash Equivalents, Short-term and Long-term Investments, Fair Value

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Cash, Cash Equivalents, Short-term and Long-term Investments, Gross Unrealized Gain

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Cash, Cash Equivalents, Short-term and Long-term Investments, Gross Unrealized Loss

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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CASH, CASH EQUIVALENTS AND INVESTMENTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2017	Mar. 31, 2016
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Gross Realized Gain (Loss)	$ 1,200
Cash and cash equivalents	390,661	$ 202,509	$ 301,970	$ 235,266
Short-term investments (due in 1 year or less)	269,313	13,332
Total cash, cash equivalents and investments measured at fair value, amortized cost	660,176	215,929
Total cash, cash equivalents and investments measured at fair value, gross unrealized gain	193	197
Total cash, cash equivalents and investments measured at fair value, gross unrealized loss	(395)	(285)
Total cash, cash equivalents and investments measured at fair value, fair value	659,974	215,841
Level 1
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	30,522	0
Short-term investments (due in 1 year or less)	112,597	13,332
Debt Securities, Available-for-sale, Amortized Cost	143,053	13,420
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	193	197
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(127)	(285)
Debt Securities, Available-for-sale	143,119	13,332
Level 2
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	51,405
Short-term investments (due in 1 year or less)	156,716
Total cash, cash equivalents and investments measured at fair value, amortized cost	208,389
Total cash, cash equivalents and investments measured at fair value, gross unrealized gain	0
Total cash, cash equivalents and investments measured at fair value, gross unrealized loss	(268)
Total cash, cash equivalents and investments measured at fair value, fair value	208,121
Cash
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	308,734	202,509
Money Market Funds [Member] \| Level 1
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	344
Available-for-sale Securities, fair value		0
Short-term investments (due in 1 year or less)	0
Debt Securities, Available-for-sale, Amortized Cost	344
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0
Debt Securities, Available-for-sale	344
Mutual Funds \| Level 1
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	0	0
Short-term investments (due in 1 year or less)	13,455	13,332
Debt Securities, Available-for-sale, Amortized Cost	13,336	13,420
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	186	197
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(67)	(285)
Debt Securities, Available-for-sale	13,455	13,332
US Treasury Notes \| Level 1
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	30,178	0
Available-for-sale Securities, amortized cost basis		0
Available-for-sale Securities, gross unrealized gains		0
Available-for-sale Securities, gross unrealized losses		0
Available-for-sale Securities, fair value		0
Short-term investments (due in 1 year or less)	99,142	$ 0
Debt Securities, Available-for-sale, Amortized Cost	129,373
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	7
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(60)
Debt Securities, Available-for-sale	129,320
Commercial Paper-not included in Cash and Cash Equivalents \| Level 2
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	6,978
Short-term investments (due in 1 year or less)	39,320
Debt Securities, Available-for-sale, Amortized Cost	46,354
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(56)
Debt Securities, Available-for-sale	46,298
Municipal Bonds \| Level 2
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	3,591
Short-term investments (due in 1 year or less)	0
Debt Securities, Available-for-sale, Amortized Cost	3,591
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0
Debt Securities, Available-for-sale	3,591
Corporate Bonds \| Level 2
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	0
Short-term investments (due in 1 year or less)	54,489
Debt Securities, Available-for-sale, Amortized Cost	54,701
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(212)
Debt Securities, Available-for-sale	54,489
Commercial Paper \| Level 2
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	40,836
Short-term investments (due in 1 year or less)	43,676
Debt Securities, Available-for-sale, Amortized Cost	84,512
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0
Debt Securities, Available-for-sale	84,512
Certificates of Deposits (CDs) \| Level 2
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	0
Short-term investments (due in 1 year or less)	19,231
Debt Securities, Available-for-sale, Amortized Cost	19,231
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0
Debt Securities, Available-for-sale	$ 19,231