NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS - Changes in Benefit Obligations and Fair Value of Plan (Details) - USD ($) $ in Thousands	2 Months Ended	12 Months Ended
Dec. 31, 2017	Dec. 31, 2018
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation, beginning of period	$ 10,515	$ 11,484
Service cost	68	449
Interest cost	25	150
Participant contributions	5	5
Benefits paid	(3)	(23)
Net actuarial loss on obligation	562	(414)
Curtailment	0	(553)
Settlement	0	(250)
Currency loss	312	0
Projected benefit obligation, end of year	11,484	10,848
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of period	3,776	3,893
Actual return on plan assets	(8)	(53)
Employer contributions	22	292
Participant contributions	5	5
Administrative expenses	(4)	(22)
Benefits paid	(3)	(273)
Currency gain	105	0
Fair value of plan assets, end of year	3,893	3,842
Funded status at end of year	(7,591)	(7,006)
Net actuarial loss	578	222
Liability, Defined Benefit Plan [Abstract]
Accrued expenses and other (current pension liability)	(67)	(75)
Other long-term liabilities (non-current pension liability)	(7,524)	(6,931)
Net amount recognized	$ (7,591)	$ (7,006)

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

Name:	us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.