RETIREMENT PLAN - NARRATIVE (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Retirement Benefits [Abstract]
Defined contribution plan, vesting period (in years)	3 years
Defined contribution plan, vesting percentage after 3 years (as a percent)	100.00%
Defined contribution plan, employer matching contribution (as a percent)	50.00%
Defined contribution plan, percent of employees' gross pay (as a percent)	3.00%
Company matching contributions	$ 0.3	$ 0.3	$ 0.2

Defined Contribution Plan, Employers Matching Contribution, Vesting Percentage After Three Years

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Defined Contribution Plan, Employers Matching Contribution, Vesting Period

No definition available.

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No definition available.

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Amount of discretionary contributions made by an employer to a defined contribution plan.

No definition available.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

No definition available.

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Percentage employer matches of the employee's percentage contribution matched.

No definition available.

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