BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Adoption of ASU 2016-15 (Details) - USD ($) $ in Thousands	6 Months Ended
	Oct. 31, 2018	Oct. 31, 2017
Business Acquisition [Line Items]
Net cash provided by operating activities	$ 27,214	$ 27,733
Net cash provided by (used by) investing activities	43,727	(119,702)
Net cash provided by (used by) financing activities	(69,195)	81,415
Net increase (decrease) in cash, cash equivalents		0
Net increase (decrease) in cash, cash equivalents, and restricted cash	1,746	(10,554)
Cash and cash equivalents at beginning of period	11,891	0
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH AT BEGINNING OF PERIOD	16,116	56,800
Cash and cash equivalents at end of period	12,777
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH AT END OF PERIOD	$ 17,862	46,246
Previously Reported [Member]
Business Acquisition [Line Items]
Net cash provided by operating activities		26,932
Net cash provided by (used by) investing activities		(95,112)
Net cash provided by (used by) financing activities		81,825
Net increase (decrease) in cash, cash equivalents		13,645
Net increase (decrease) in cash, cash equivalents, and restricted cash		0
Cash and cash equivalents at beginning of period		28,819
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH AT BEGINNING OF PERIOD		0
Cash and cash equivalents at end of period		42,464
Adjustment [Member] | Accounting Standards Update 2016-15 [Member]
Business Acquisition [Line Items]
Net cash provided by operating activities		801
Net cash provided by (used by) investing activities		(24,590)
Net cash provided by (used by) financing activities		(410)
Net increase (decrease) in cash, cash equivalents		(13,645)
Net increase (decrease) in cash, cash equivalents, and restricted cash		(10,554)
Cash and cash equivalents at beginning of period		(28,819)
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH AT BEGINNING OF PERIOD		56,800
Cash and cash equivalents at end of period
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH AT END OF PERIOD		$ 3,782