Income Taxes - Reconciliation Between Effective Income Tax Rate and PRC Statutory Income Tax Rate (Details)		12 Months Ended
Jan. 01, 2008	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Effective Income Tax Rate Continuing Operations Tax Rate Reconciliation [Abstract]
PRC statutory tax rate	25.00%	25.00%	25.00%	25.00%	25.00%
Withholding tax on the PRC earnings distribution		10.00%	0.00%	3.00%
Effect of international rate difference		1.00%	1.00%	0.00%
Effect of preferential tax rate		(7.00%)	0.00%	(5.00%)
Tax effect of expenses that are not deductible in determining taxable profit		20.00%	5.00%	7.00%
Effective tax rate		49.00%	31.00%	30.00%

Effective income tax rate reconciliation effect of preferential tax rate.

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.Fact.4)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

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-Section S99
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-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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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 attributable to deduction for dividend.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.Fact.4)
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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