CONTINGENCIES AND COMMITMENTS (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Commitments And Contingencies Disclosure Abstract
Letter of credit requirement	$ 5,862	$ 5,862
OtherCommitmentsLineItems
RestrictedCash	69,365	0
CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents			$ 34,770
Total Proceeds	70,200
Cash and Cash Equivalents Member
OtherCommitmentsLineItems
Cash	122,893	68,266
RestrictedCash	69,365	0
CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	$ 192,258	$ 68,266

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 50
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-Section 45
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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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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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Amount of cash 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02(1))
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-Name Accounting Standards Codification
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-Section S99
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