REVENUE RECOGNITION - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Deferred revenue			$ 332,200
Deferred revenue recognized during period	$ 224,000	$ 278,800
Deferred revenue	375,138	375,138		$ 342,483
Noncurrent deferred revenue	2,000	2,000
Amortization expense recognized related to contract cost assets	84,700	159,800
Capitalization of costs incurred to obtain contract	$ 72,800	$ 72,800

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

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-Publisher FASB
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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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