11. SUBSEQUENT EVENTS	9 Months Ended
Jan. 31, 2019
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	11. SUBSEQUENT EVENTS On March 6, 2019, our Board of Directors declared a quarterly cash dividend of $0.65625 per share on our outstanding Series E Preferred Stock. The dividend payment is equivalent to an annualized 10.50% per share, based on the $25.00 per share stated liquidation preference, accruing from January 1, 2019 through March 31, 2019. The cash dividend is payable on April 1, 2019 to holders of the Series E Preferred Stock of record on March 18, 2019.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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