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Summary of Significant Accounting Policies - Intangibles (Detail)	12 Months Ended
	Dec. 31, 2018
Customer and Supplier Relationships [Member]
Significant accounting policies
Amortizable period of the intangible assets	10 years
Covenants not-to-compete [Member] | Minimum [Member]
Significant accounting policies
Amortizable period of the intangible assets	2 years
Covenants not-to-compete [Member] | Maximum [Member]
Significant accounting policies
Amortizable period of the intangible assets	5 years

X

- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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X

- Definition

Significant Accounting Policies [Line Items]

+ References

No definition available.

+ Details

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- Details

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- Details

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