COMMITMENTS AND CONTINGENCIES - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2018
Loss Contingencies [Line Items]
Reductions to FI share, 2018		$ 5.4
Reductions to FI share, 2019		4.6
Amounts not yet paid to FI		9.0
FI share, expense	$ 1.5
Financial Institution Share Commitment
Loss Contingencies [Line Items]
FI share commitment		$ 10.0

Deferred Implementation Costs, Amortization Expense, Current Fiscal Year

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- Definition

Deferred Implementation Costs, Amortization Expense, Year Two

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- Definition

Financial Institution Partners, Unearned Amounts Not Yet Paid

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- Definition

Financial Institution Share, Expense

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- Definition

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.

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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

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No definition available.

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