Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Name:	us-gaap_RestrictedCashAndCashEquivalents
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Schedule of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2016
Restricted Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents	$ 26,579	$ 13,792	$ 11,891
Restricted cash	19,538	5,464	4,225
Total cash, cash equivalents and restricted cash	46,117	$ 19,256	$ 16,116	$ 56,800	$ 71,508
Tax-Deferred Exchange Proceeds
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	17,200
Escrow Deposits
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 2,300