Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 216,163us-gaap_ProfitLoss	$ 97,849us-gaap_ProfitLoss	$ 46,471us-gaap_ProfitLoss
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(17,210)	11,104	2,849
Unrealized loss on available-for-sale investments	(15,876)	0	0
Other comprehensive income (loss)	(33,086)	11,104	2,849
Comprehensive income	183,077	108,953	49,320
Add: Comprehensive loss attributable to noncontrolling interest	7,539	1,965	277
Comprehensive income attributable to Qihoo 360 Technology Co. Ltd.	$ 190,616us-gaap_ComprehensiveIncomeNetOfTax	$ 110,918us-gaap_ComprehensiveIncomeNetOfTax	$ 49,597us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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