Employee Benefits - Additional Information (Detail) (USD $)	12 Months Ended																							1 Months Ended	12 Months Ended															1 Months Ended	12 Months Ended		1 Months Ended		12 Months Ended			12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Stock Options	Dec. 31, 2012 Stock Options	Dec. 31, 2011 Stock Options	Dec. 31, 2013 Employee Stock Purchase Plan	Dec. 31, 2012 Employee Stock Purchase Plan	Dec. 31, 2011 Employee Stock Purchase Plan	Dec. 31, 2013 Restricted Stock Awards And Units	Dec. 31, 2012 Restricted Stock Awards And Units	Dec. 31, 2011 Restricted Stock Awards And Units	Dec. 31, 2013 Director	Dec. 31, 2013 Director Options Granted After May 252006 Y	Dec. 31, 2013 Minimum	Dec. 31, 2013 Maximum	Dec. 31, 2013 Maximum 1995 Stock Plan	Dec. 31, 2013 Initial Grant Director Options Granted Before May 252006	Dec. 31, 2013 Annual Grant Director Options Granted Before May 252006 Installment	Dec. 31, 2013 Annual Grant Minimum Director Options Granted Before May 252006 Y	Dec. 31, 2013 Annual Grant Maximum Director Options Granted Before May 252006 Y	Dec. 31, 2013 Prior to November 2012	Dec. 31, 2013 Beginning in November 2012	Nov. 30, 2013 Performance Based Stock Options CEO Two Thousand Twelve Annual Equity Awards	Dec. 31, 2013 Performance Based Stock Options CEO Two Thousand Twelve Annual Equity Awards	Dec. 31, 2013 Performance Based Stock Options CEO One-Time Retention Award	Dec. 31, 2013 Performance Based Stock Options First Tranche	Dec. 31, 2013 Performance Based Stock Options Second Tranche	Dec. 31, 2013 Performance Based Stock Options Minimum	Dec. 31, 2013 Performance Based Stock Options Maximum	Dec. 31, 2013 Performance Based Stock Options Revenue ex -TAC	Dec. 31, 2013 Performance Based Stock Options Operating Income	Dec. 31, 2013 Performance Based Stock Options Free Cash Flow	Dec. 31, 2013 Performance Based Restricted Stock Units	Dec. 31, 2013 Performance Based Restricted Stock Units Minimum	Dec. 31, 2013 Performance Based Restricted Stock Units Maximum	Dec. 31, 2013 Performance Based Restricted Stock Units Revenue ex -TAC	Dec. 31, 2013 Performance Based Restricted Stock Units Operating Income	Dec. 31, 2013 Performance Based Restricted Stock Units Free Cash Flow	Jul. 31, 2012 Restricted Stock Units (RSUs) CEO Two Thousand Twelve Annual Equity Awards	Dec. 31, 2013 Restricted Stock Units (RSUs) CEO Two Thousand Twelve Annual Equity Awards	Jul. 31, 2012 Restricted Stock Units (RSUs) CEO One-Time Retention Award	Jul. 31, 2012 Restricted Stock Units (RSUs) CEO Make-Whole Restricted Stock Units	Dec. 31, 2013 Restricted Stock Units (RSUs) CEO Make-Whole Restricted Stock Units	Dec. 31, 2013 Restricted Stock Units (RSUs) Director	Dec. 31, 2013 Stock Plan 1995	Dec. 31, 2013 Stock Plan 1995 Stock Options	Dec. 31, 2013 Stock Plan 1995 Options Granted Prior To May 192005 Y	Dec. 31, 2013 Stock Plan 1995 Options Granted After May 192005 Y	Dec. 31, 2013 Four Zero One K Plan Minimum	Dec. 31, 2013 Four Zero One K Plan Maximum	Dec. 31, 2013 401(k)	Dec. 31, 2012 401(k)	Dec. 31, 2011 401(k)	Dec. 31, 2013 Other Foreign Benefit Plans	Dec. 31, 2012 Other Foreign Benefit Plans	Dec. 31, 2011 Other Foreign Benefit Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Benefit plan employee contribution																																																		1.00%	50.00%
Rate at which the company matches employee contributions	25.00%
Employer contributions to benefit plans																																																				$ 18,000,000	$ 19,000,000	$ 20,000,000	$ 17,000,000	$ 22,000,000	$ 24,000,000
Expiration of stock awards, years														7						7	10																											10	7
Equity award vesting period														1 year	1 year	4 years	4 years	4 years							2 years 6 months	4 years 6 months															3 years	5 years			1 year
Number of shares available to be awarded							75,000,000						9,000,000																																		754,000,000
Shares available for issuance							15,000,000						5,000,000																																		65,000,000
Number of shares granted against share limits													1.75																																	1.75
Vesting period installments														Equal quarterly installments over one year				Equal monthly installments over four years
Vesting percentage upon one year anniversary of date of grant																			25.00%
Number of installments for vesting period																			36
Employee stock purchase plan payroll deductions percent																15.00%
Price as a percentage of fair value of common stock purchased under employee stock purchase plan																						85.00%	90.00%
Employee stock purchase plan offering period																						24 months	3 months
Stock-based compensation expense	278,220,000	224,365,000	203,958,000				16,000,000	31,000,000	46,000,000
Unamortized stock-based compensation expense				16,000,000			3,000,000			615,000,000
Stock-based compensation, recognition period				1 year 6 months			4 months 24 days			2 years 9 months 18 days																	6 months	12 months						1 year
Weighted-average grant date fair value of all options granted and assumed during period	$ 18.72	$ 4.36	$ 5.04
Total intrinsic value of options exercised				122,000,000	45,000,000	46,000,000
Cash received from options exercised				353,000,000
Tax benefit from stock option exercises				16,000,000
Total fair value of restricted stock awards vested										220,000,000	171,000,000	136,000,000
Vested										14,200,000
Shares withheld to settle employees' minimum statutory obligation for applicable income and other employment taxes										5,300,000
Payments made to taxing authorities for employees' tax obligations	139,815,000	60,939,000	44,761,000
Excess tax benefits from stock-based awards	64,407,000	35,844,000	70,680,000
Equity award granted																								6,000,000																6,000,000			14,000,000
Equity award expected grant date																									2012-11	2012-11
Equity award granted																																										15,000,000
Equity award expected to be granted																										15,000,000
Equity award vesting in 2012																																												4,000,000
Equity award vesting in 2013																																												7,000,000
Equity award vesting in 2014																																												3,000,000
Stock awards vesting percentage for each performance period																													0.00%	100.00%					0.00%	200.00%
Financial performance metrics for stock option awards																															50.00%	30.00%	20.00%
Stock options grant date fair value																											12,000,000	14,000,000
Financial performance metrics for restricted stock units awards																																					60.00%	20.00%	20.00%
Restricted stock units grant date fair value																																		$ 9,000,000