ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Recently Adopted and Issued Accounting Pronouncements (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Jan. 01, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Investment, long-term loan receivable		$ 3,500
Expected allowance for credit loss	$ 1,900
Convertible debt
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reacquisition of equity component	16,814
2.5% Convertible Notes debt 2021 \| Convertible debt
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reacquisition of equity component	300
5.0% Convertible Notes debt 2024 \| Convertible debt
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reacquisition of equity component	$ 16,800

Financing Receivable, Expected Allowance For Credit Loss

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- Definition

Adjustment to additional paid in capital resulting from the recognition of convertible debt instruments as two separate components - a debt component and an equity component. This bifurcation may result in a basis difference associated with the liability component that represents a temporary difference for purposes of applying accounting for income taxes. The initial recognition of deferred taxes for the tax effect of that temporary difference is as an adjustment to additional paid in capital.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 25
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=51819886&loc=SL6014347-161799

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Amount, before allowance for credit loss, of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919230-210447

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