FAIR VALUE MEASUREMENTS - ROLLFORWARD OF FAIR VALUE OF ASSETS (Details)	3 Months Ended
Mar. 31, 2016 USD ($)
Roll forward of the fair value of the Company's investments whose fair value was determined using Level 3 inputs
Transfers between the levels	$ 0
Balance at the beginning of the period	57,121,000
Balance at the end of the period	58,151,000
Fair Value Of Contingent Consideration
Roll forward of the fair value of the Company's investments whose fair value was determined using Level 3 inputs
Increase (decrease) in fair value	1,900,000
Other income (expense)
Roll forward of the fair value of the Company's investments whose fair value was determined using Level 3 inputs
Increase (decrease) in fair value	$ (870,000)

Represents the fair value of asset or liability transfers in a recurring basis between the levels.

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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