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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Contractual interest rate for funds borrowed, under the debt agreement.

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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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No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Long-Term Debt - Summary of Long-Term Debt Carrying Values Including Unamortized Discounts and Premiums (Detail) - USD ($) $ in Thousands	Aug. 31, 2018	Apr. 30, 2018	Nov. 30, 2017
Debt Instrument [Line Items]
Long-term debt	$ 6,574,866		$ 6,416,844
3.875% Convertible Senior Debentures
Debt Instrument [Line Items]
Debt instrument interest rate	3.875%
Unsecured Debt
Debt Instrument [Line Items]
Long-term debt	$ 6,416,388		6,416,844
Unsecured Debt \| 5.125% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 0	$ 668,300	682,338
Debt instrument interest rate	5.125%
Effective Interest Rate	0.00%
Unsecured Debt \| 8.500% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 707,072		728,872
Debt instrument interest rate	8.50%
Effective Interest Rate	3.99%
Unsecured Debt \| 2.375% Euro Medium Term Notes
Debt Instrument [Line Items]
Long-term debt	$ 578,896		593,334
Debt instrument interest rate	2.375%
Effective Interest Rate	2.42%
Unsecured Debt \| 6.875% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 795,967		808,157
Debt instrument interest rate	6.875%
Effective Interest Rate	4.40%
Unsecured Debt \| 2.250% Euro Medium Term Notes
Debt Instrument [Line Items]
Long-term debt	$ 4,332		4,389
Debt instrument interest rate	2.25%
Effective Interest Rate	4.08%
Unsecured Debt \| 5.125% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 613,634		615,703
Debt instrument interest rate	5.125%
Effective Interest Rate	4.55%
Unsecured Debt \| 4.850% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 712,667		736,357
Debt instrument interest rate	4.85%
Effective Interest Rate	4.93%
Unsecured Debt \| 6.450% Senior Debentures
Debt Instrument [Line Items]
Long-term debt	$ 374,211		375,794
Debt instrument interest rate	6.45%
Effective Interest Rate	5.46%
Unsecured Debt \| 3.875% Convertible Senior Debentures
Debt Instrument [Line Items]
Long-term debt	$ 0		324,779
Debt instrument interest rate	3.875%
Effective Interest Rate	0.00%
Unsecured Debt \| 4.150% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 987,576		0
Debt instrument interest rate	4.15%
Effective Interest Rate	4.26%
Unsecured Debt \| 6.250% Senior Debentures
Debt Instrument [Line Items]
Long-term debt	$ 511,758		512,040
Debt instrument interest rate	6.25%
Effective Interest Rate	6.03%
Unsecured Debt \| 6.500% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 420,718		420,990
Debt instrument interest rate	6.50%
Effective Interest Rate	6.09%
Unsecured Debt \| Structured notes
Debt Instrument [Line Items]
Long-term debt	$ 709,557		614,091
Secured Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt	$ 158,478		$ 0