Aggregate undistributed earnings available for distribution to parent company

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Corporate Income Tax Rate [Line Items]

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Income tax exemption period for software enterprise entitled to the preferential tax treatment according to PRC government authorities.

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The number of years during which the Company enjoys 50% interest rate.

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Income tax rate approved by the local tax authority to file its income tax by adopting the "deemed-profit method".

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Income Taxes Preferential Tax Rate

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- Definition

Income Taxes Reduction Percentage

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Positive Impact of Tax Holidays on Basic Net Income Per Ordinary Share

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Withholding taxes rate on remittance of dividends

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- Definition

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 state and local income tax expense (benefit), net of federal tax expense (benefit).

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Amount 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 income exempt from income tax because of a tax holiday.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Income Taxes (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Corporate Income Tax Rate [Line Items]
Income tax expense increased without tax holidays	$ 56,049	$ 58,529	$ 43,460
Positive impact of tax holidays on basic net income per ordinary share	$ 0.30	$ 0.32	$ 0.24
Hong Kong [Member]
Corporate Income Tax Rate [Line Items]
Unified income tax rate	16.50%	16.50%	16.50%
Singapore [Member]
Corporate Income Tax Rate [Line Items]
Unified income tax rate	17.00%	17.00%	17.00%
United States of America ("USA") [Member]
Corporate Income Tax Rate [Line Items]
Withholding taxes rate on remittance of dividends	30.00%
United States of America ("USA") [Member] \| Minimum [Member]
Corporate Income Tax Rate [Line Items]
Unified income tax rate	15.00%	15.00%	15.00%
United States of America ("USA") [Member] \| Maximum [Member]
Corporate Income Tax Rate [Line Items]
Unified income tax rate	39.00%	39.00%	39.00%
Delaware [Member]
Corporate Income Tax Rate [Line Items]
State income tax rate in Delaware	8.70%	8.70%	8.70%
PRC [Member]
Corporate Income Tax Rate [Line Items]
Unified income tax rate	25.00%	25.00%	25.00%
Income tax rate under deemed-profit method	2.50%
PRC [Member] \| HNTE [Member]
Corporate Income Tax Rate [Line Items]
Preferential tax rate	15.00%
PRC [Member] \| Software Enterprise [Member]
Corporate Income Tax Rate [Line Items]
Preferential tax rate	12.50%
Income tax holiday, exemption period as Software Enterprise	2 years
Income taxes reduction percentage	50.00%
Income tax holiday, half rate period as Software Enterprise	3 years
PRC [Member] \| Qizhi Software [Member] \| HNTE [Member]
Corporate Income Tax Rate [Line Items]
Preferential tax rate	15.00%	15.00%	15.00%
PRC [Member] \| Beijing Qihu [Member] \| HNTE [Member]
Corporate Income Tax Rate [Line Items]
Preferential tax rate	15.00%	15.00%	15.00%
PRC [Member] \| Beijing Star World [Member] \| HNTE [Member]
Corporate Income Tax Rate [Line Items]
Preferential tax rate	15.00%	15.00%	15.00%
PRC [Member] \| Tianjin Qisi [Member] \| HNTE [Member]
Corporate Income Tax Rate [Line Items]
Preferential tax rate	15.00%
PRC [Member] \| Tianjin Qisi [Member] \| Software Enterprise [Member]
Corporate Income Tax Rate [Line Items]
Preferential tax rate		12.50%
Income tax holiday, exemption period as Software Enterprise			2 years
PRC [Member] \| Qifei Xiangyi [Member] \| HNTE [Member]
Corporate Income Tax Rate [Line Items]
Preferential tax rate	15.00%
PRC [Member] \| Qifei Xiangyi [Member] \| Software Enterprise [Member]
Corporate Income Tax Rate [Line Items]
Income tax holiday, exemption period as Software Enterprise		2 years	2 years
PRC [Member] \| Other VIEs and VIEs' subsidiaries [Member]
Corporate Income Tax Rate [Line Items]
Unified income tax rate	25.00%
PRC [Member] \| The Company and its subsidiaries, VIEs and VIEs' subsidiaries registered outside the PRC [Member] \| Pro Forma [Member]
Corporate Income Tax Rate [Line Items]
Unified income tax rate	25.00%
Withholding taxes rate on remittance of dividends	10.00%
PRC [Member] \| Subsidiaries and VIEs [Member]
Corporate Income Tax Rate [Line Items]
Aggregate undistributed earnings available for distribution to the Company	$ 1,003,287
Total net operating loss carry forwards	$ 229,952