INVESTMENTS - Schedule of Activity for Available For Sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, Amortized Cost	$ 9,961	$ 25,636
Available-for-sale securities, Gross Unrealized Gain	246	1,653
Available-for-sale securities, Gross Unrealized Loss	0	(504)
Available-for-sale securities, Fair Value	(10,207)	(26,785)
Convertible Debt Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, Amortized Cost	0	10,205
Available-for-sale securities, Gross Unrealized Gain	0	1,653
Available-for-sale securities, Gross Unrealized Loss	0	(504)
Available-for-sale securities, Fair Value	0	(11,354)
Redeemable Preferred Stock
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, Amortized Cost	9,961	15,431
Available-for-sale securities, Gross Unrealized Gain	246	0
Available-for-sale securities, Gross Unrealized Loss	0	0
Available-for-sale securities, Fair Value	$ (10,207)	$ (15,431)

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

No definition available.

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Balance Type:	debit
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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

+ Details

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

+ Details

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

+ Details

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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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