LONG-TERM DEBT (Components of Long-Term Debt) (Details) - USD ($) $ in Thousands	Jan. 31, 2020	Apr. 30, 2019	Jan. 31, 2019
Debt Instrument [Line Items]
Committed line of credit borrowings	$ 1,035,000	$ 0	$ 385,000
Debt issuance costs and discounts	(5,389)	(7,371)	(8,011)
Long-term debt including current portion	2,529,611	1,492,629	1,876,989
Less: Current portion	(649,022)	0	0
Long-term debt and line of credit borrowings	$ 1,880,589	1,492,629	1,876,989
Senior Notes \| Senior Notes, 4.125%, due October 2020
Debt Instrument [Line Items]
Interest rate	4.125%
Senior notes	$ 650,000	650,000	650,000
Senior Notes \| Senior Notes, 5.500%, due November 2022
Debt Instrument [Line Items]
Interest rate	5.50%
Senior notes	$ 500,000	500,000	500,000
Senior Notes \| Senior Notes, 5.250%, due October 2025
Debt Instrument [Line Items]
Interest rate	5.25%
Senior notes	$ 350,000	$ 350,000	$ 350,000

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

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- Definition

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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No definition available.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

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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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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