COMMITMENTS, CONTINGENCIES AND REGULATORY MATTERS - Lease Activity (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019
Lessee, Lease, Description [Line Items]
Cash used in operating activities for amounts included in the measurement of lease liabilities	$ 3,720	$ 8,457
Short-term (less than one year) lease costs	1,152	2,309
Selling, general and administrative expense
Lessee, Lease, Description [Line Items]
Operating lease costs	2,385	5,265
Cost of revenue
Lessee, Lease, Description [Line Items]
Operating lease costs	$ 670	$ 1,528

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.

No definition available.

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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-Publisher FASB
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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

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- Definition

Amount of short-term lease cost, excluding expense for lease with term of one month or less.

+ References

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-Publisher FASB
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