Stockholders Equity - Additional Information (Detail) (USD $)	12 Months Ended						1 Months Ended		12 Months Ended			12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2006	Dec. 31, 2011 Elong	May 31, 2011 Elong	May 31, 2011 Tencent Holdings	Feb. 04, 2013 Dividend Declared Q1 2013	Dec. 31, 2011 Series A Preferred Stock	Dec. 31, 2012 Common Stock	Dec. 31, 2011 Common Stock	Dec. 31, 2012 Common Class B	Dec. 31, 2011 Common Class B
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized										1,600,000,000	1,600,000,000	400,000,000	400,000,000
Common stock, par value										$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Number of voting rights to each shareholder, per share										1		10
Total number of directors elected by holders of common stock, voting as single class, percentage	25.00%
Preferred stock, par value									$ 22.23
Preferred stock merger cash payment									$ 17,000
Authorized share repurchase	20,000,000		20,000,000	20,000,000
Total authorized share repurchased	60,000,000
Shares authorized and remaining under the repurchase program	18,100,000
Dividends declaration date								Feb. 04, 2013
Dividends per share								$ 0.13
Dividends payable date								Mar. 28, 2013
Dividends record date								Mar. 11, 2013
Net reduction in additional paid in capital		(647,528,000)
Additional ownership interest purchased, price					93,000,000	41,000,000
Additional ownership interest purchased, percent							16.00%
Ownership interest, purchase price							84,000,000
Acquired additional interest of majority owned subsidiaries		$ 22,000,000	$ 78,000,000
Ownership interest percentage	67.00%	67.00%