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

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

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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 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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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.

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CASH, CASH EQUIVALENTS, AND INVESTMENTS (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	$ 280,350	$ 232,704	$ 235,534	$ 228,776
Short-term investments (due in 1 year or less)	90,647us-gaap_ShortTermInvestments	102,717us-gaap_ShortTermInvestments
Long-term investments (due in 1 to 3 years)	112,796us-gaap_LongTermInvestments	100,342us-gaap_LongTermInvestments
Total cash, cash equivalents and investments measured at fair value, amortized cost	483,750	435,516
Total cash, cash equivalents and investments measured at fair value, gross unrealized gains	242	276
Total cash, cash equivalents and investments measured at fair value, gross unrealized losses	(199)	(29)
Total cash, cash equivalents and investments measured at fair value, fair value	483,793	435,763
Cash [Member]
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	275,851	232,704
Level 1 [Member] \| Mutual Funds [Member]
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, amortized cost basis	4,757	1,779
Available-for-sale Securities, gross unrealized gains	121	31
Available-for-sale Securities, gross unrealized losses	(75)	(3)
Available-for-sale Securities, fair value	4,803	1,807
Short-term investments (due in 1 year or less)	4,803	1,807
Long-term investments (due in 1 to 3 years)	0	0
Level 2 [Member]
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	4,499
Available-for-sale Securities, amortized cost basis	203,142	201,033
Available-for-sale Securities, gross unrealized gains	121	245
Available-for-sale Securities, gross unrealized losses	(124)	(26)
Available-for-sale Securities, fair value	203,139	201,252
Short-term investments (due in 1 year or less)	85,844	100,910
Long-term investments (due in 1 to 3 years)	112,796	100,342
Level 2 [Member] \| Government Agency Securities [Member]
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, amortized cost basis	85,139	53,976
Available-for-sale Securities, gross unrealized gains	14	43
Available-for-sale Securities, gross unrealized losses	(67)	(9)
Available-for-sale Securities, fair value	85,086	54,010
Short-term investments (due in 1 year or less)	32,235	21,325
Long-term investments (due in 1 to 3 years)	52,851	32,685
Level 2 [Member] \| Commercial Paper [Member]
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Cash and cash equivalents	4,499
Available-for-sale Securities, amortized cost basis	18,589	47,766
Available-for-sale Securities, gross unrealized gains	3	7
Available-for-sale Securities, gross unrealized losses	0	0
Available-for-sale Securities, fair value	18,592	47,773
Short-term investments (due in 1 year or less)	14,093	47,773
Long-term investments (due in 1 to 3 years)	0	0
Level 2 [Member] \| Corporate Bonds [Member]
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, amortized cost basis	99,414	98,289
Available-for-sale Securities, gross unrealized gains	104	195
Available-for-sale Securities, gross unrealized losses	(57)	(17)
Available-for-sale Securities, fair value	99,461	98,467
Short-term investments (due in 1 year or less)	39,516	30,810
Long-term investments (due in 1 to 3 years)	59,945	67,657
Level 2 [Member] \| CDs [Member]
Schedule of Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, amortized cost basis		1,002
Available-for-sale Securities, gross unrealized gains		0
Available-for-sale Securities, gross unrealized losses		0
Available-for-sale Securities, fair value		1,002
Short-term investments (due in 1 year or less)		1,002
Long-term investments (due in 1 to 3 years)		$ 0