DEBT - Schedule of future payments (Details) $ in Thousands	6 Months Ended
Oct. 31, 2018 USD ($) property loan	Apr. 30, 2018 USD ($)
Debt Instrument [Line Items]
Number of real estate properties \| property	93
Aggregate amount of required future principal payments on mortgages payable [Abstract]
Total payments	$ 447,549	$ 509,919
Mortgages [Member]
Debt Instrument [Line Items]
Number of loans in default \| loan	0
Aggregate amount of required future principal payments on mortgages payable [Abstract]
2019	$ 4,870
2020	71,833
2021	92,177
2022	70,506
2023	27,494
Thereafter	182,534
Total payments	$ 449,414
Multifamily [Member]
Debt Instrument [Line Items]
Number of real estate properties serving as collateral \| property	52

Refers to number of loans in default

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Number Of Real Estate Properties, Collateral

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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.

+ References

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-Publisher FASB
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-Topic 470
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

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