BUSINESS COMBINATIONS - Allocation of Aggregate Acquisition Price (Details) - Cloud Savings - USD ($) $ in Thousands	Apr. 30, 2018	Sep. 30, 2018
Business Acquisition [Line Items]
Cash and cash equivalents	$ 6,244
Accounts receivable	5,885
Prepaid expenses and other current assets	804
Property, equipment and software	226
Goodwill		$ 46,217
Other intangible assets	83,543
Accounts payable	693
Accrued merchant and supplier payables	386
Accrued expenses and other current liabilities	6,130
Other non-current liabilities	2,076
Total liabilities assumed	9,285
Total acquisition price	74,258
Merchant relationships
Business Acquisition [Line Items]
Intangible assets (1) :	20,322
Developed technology
Business Acquisition [Line Items]
Intangible assets (1) :	549
Other intangible assets
Business Acquisition [Line Items]
Intangible assets (1) :	687
Trade names
Business Acquisition [Line Items]
Intangible assets (1) :	$ 2,609

Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Assets, Including Goodwill

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Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Accrued Merchant and Supplier Payables

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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