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Future Impact of Recently Issued Accounting Standards Not Yet in Effect - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2018
Bottom of range [member]
Disclosure of impact of new accounting standards [line items]
Percentage of right-of-use assets	8.50%
Top of range [member]
Disclosure of impact of new accounting standards [line items]
Percentage of right-of-use assets	9.50%

X

- Definition

Line items represents impact of new accounting standards.

+ References

No definition available.

+ Details

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X

- Definition

Percentage of right-of-use assets.

+ References

No definition available.

+ Details

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X

- Details

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Period Type:

X

- Details

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Period Type: