Reconciliation of United States Statutory Rates to Effective Rate (Detail)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Reconciliation Of Effective Income Tax Rate [Line Items]
US statutory rate	34.00%	34.00%
Foreign income and loss not recognized in U.S.A.	(34.00%)	(34.00%)
China income tax	25.00%	25.00%
Miscellanies and non-deductible expense	1.00%	(2.30%)
Effective tax rate	26.00%	22.70%

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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