COMMITMENTS, CONTINGENCIES AND REGULATORY MATTERS - Lease Activity (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Lessee, Lease, Description [Line Items]
Cash used in operating activities for amounts included in the measurement of lease liabilities	$ 4,737
Short-term (less than one year) lease costs	1,157
Selling, general and administrative expense
Lessee, Lease, Description [Line Items]
Operating lease costs	2,880
Cost of revenue
Lessee, Lease, Description [Line Items]
Operating lease costs	$ 858

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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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.

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

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