Summary of % of Revenues and A/R from Major Customers (Details)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
T.I. Group Automotive Systems
Percentage of revenues from major customers	17.00%	19.00%
Percentage of accounts receivable balances	15	25
Cooper Standard
Percentage of revenues from major customers	10.00%
Percentage of accounts receivable balances	12
Parker Hannifin
Percentage of revenues from major customers	10.00%
Percentage of accounts receivable balances	17

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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