v3.8.0.1

Debt and Credit Facility Debt Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Mar. 31, 2017	Feb. 28, 2017	Feb. 28, 2015
Debt Instrument [Line Items]
Credit Facility		$ 0
Long-term debt, gross	$ 4,498,600	4,513,800
Total Convertible Debt	4,498,600	4,513,800
Less: Debt discount	(1,437,700)	(1,516,500)
Less: Debt issuance costs	(43,000)	(46,800)	$ (33,700)
Net long-term debt including current maturities	3,017,900	2,950,500
Current portion of long-term debt	(5,980)	(49,952)
Net long-term debt	3,011,852	2,900,524
December 2015 Amended Credit Facility with Maturity Dates of June 2018 and February 2020
Debt Instrument [Line Items]
Credit Facility	0	0
Less: Debt issuance costs	$ (7,000)	(8,500)
2017 Senior Subordinated Convertible Debt
Debt Instrument [Line Items]
Coupon Interest Rate	1.625%
Effective Interest Rate	6.00%
Fair Value of Liability Component at Issuance (1)	$ 1,396,300
Long-term debt, gross	2,070,000	2,070,000
Less: Debt discount	(642,200)	(667,500)
Less: Debt issuance costs	$ (16,900)	(17,600)
2015 Senior Subordinated Convertible Debt
Debt Instrument [Line Items]
Coupon Interest Rate	1.625%
Effective Interest Rate	5.90%
Fair Value of Liability Component at Issuance (1)	$ 1,160,100
Long-term debt, gross	1,725,000	1,725,000
Less: Debt discount	(423,800)	(446,600)
Less: Debt issuance costs	$ (15,700)	(16,600)
2017 Junior Subordinated Convertible Debt
Debt Instrument [Line Items]
Coupon Interest Rate	2.25%
Effective Interest Rate	7.40%
Fair Value of Liability Component at Issuance (1)	$ 321,100
Long-term debt, gross	686,300	575,000
Less: Debt discount	(360,500)	(309,300)
Less: Debt issuance costs	$ (3,300)	(3,400)		$ (30,300)
2007 Junior Subordinated Convertible Debt
Debt Instrument [Line Items]
Coupon Interest Rate	2.125%
Effective Interest Rate	9.10%
Fair Value of Liability Component at Issuance (1)	$ 6,100
Long-term debt, gross	17,300	143,800
Less: Debt discount	(11,200)	(93,100)
Less: Debt issuance costs	$ (100)	$ (700)

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. Fair value of junior subordinated convertible debenture at the balance sheet date.

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Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Fair value of the amount outstanding under the credit facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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