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Disclosure of Accounted Total Revenues Percentage (Detail) - Sales Revenue, Net - Customer Concentration Risk	4 Months Ended	5 Months Ended	12 Months Ended
	Jul. 31, 2017	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Chevron Corporation
Entity Wide Revenue Major Customer [Line Items]
Total revenue percentage	17.50%	17.40%	13.00%	15.00%
Saudi Aramco
Entity Wide Revenue Major Customer [Line Items]
Total revenue percentage	11.70%	10.10%	7.60%	8.30%

X

- Definition

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.

+ References

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- Definition

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+ References

No definition available.

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