REVENUE FROM CONTRACTS WITH CUSTOMERS - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)
Disaggregation of Revenue [Line Items]
Increase (decrease) in contract assets	$ 4,158
Increase (decrease) in contract liabilities	2,245
Revenue recognized	$ 1,100
Minimum | Parts
Disaggregation of Revenue [Line Items]
Customer payment terms	30 days
Minimum | Tooling
Disaggregation of Revenue [Line Items]
Customer payment terms	30 days
Maximum | Parts
Disaggregation of Revenue [Line Items]
Customer payment terms	90 days
Maximum | Tooling
Disaggregation of Revenue [Line Items]
Customer payment terms	90 days