Net Income Per Share (Schedule of Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	1 Months Ended	3 Months Ended			9 Months Ended
	May. 31, 2015	Sep. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Apr. 02, 2015
Numerator
Less: Adjustment Payment to Class C capital stockholders		$ 0		$ 0	$ (522)	$ 0
Allocation of undistributed earnings - continuing operations		3,979	$ 3,515	2,924	11,425	9,912
Allocation of undistributed earnings - discontinued operations		0		(185)	0	(451)
Net income		3,979	$ 3,515	$ 2,739	11,425	$ 9,461
Denominator
Continuing operations (in dollars per share)			$ 5.16	$ 4.32		$ 14.69
Net income per share - basic (in dollars per share)			$ 5.16	$ 4.05		$ 14.02
Numerator
Adjustment Payment to Class C capital stockholders		0		$ 0	(522)	$ 0
Allocation of undistributed earnings - continuing operations		3,979	$ 3,515	2,924	11,425	9,912
Allocation of undistributed earnings - discontinued operations		0		$ (185)	0	$ (451)
Weighted-average effect of dilutive securities
Continuing operations (in dollars per share)			$ 5.10	$ 4.25		$ 14.44
Net income per share - diluted (in dollars per share)			$ 5.10	$ 3.98		$ 13.78
Class C adjustment payment							$ 522
Adjustment Payment to Class C capital stockholders					47	$ 0
Class A Common Stock
Numerator
Less: Adjustment Payment to Class C capital stockholders					0	0
Allocation of undistributed earnings - continuing operations		1,683		$ 1,226	4,604	4,142
Allocation of undistributed earnings - discontinued operations		0		(78)	0	(188)
Net income		$ 1,683		$ 1,148	$ 4,604	$ 3,954
Denominator
Number of shares used in basic computation		290,368		283,850	288,686	282,014
Continuing operations (in dollars per share)		$ 5.80		$ 4.32	$ 15.95	$ 14.69
Discontinued operations (in dollars per share)		0.00		(0.27)	0.00	(0.67)
Net income per share - basic (in dollars per share)		$ 5.80		$ 4.05	$ 15.95	$ 14.02
Numerator
Adjustment Payment to Class C capital stockholders					$ 0	$ 0
Allocation of undistributed earnings - continuing operations		$ 1,683		$ 1,226	4,604	4,142
Allocation of undistributed earnings - discontinued operations		$ 0		$ (78)	$ 0	$ (188)
Denominator
Number of shares used in basic computation		290,368		283,850	288,686	282,014
Weighted-average effect of dilutive securities
Conversion of Class B to Class A common shares outstanding		51,369		54,623	52,108	55,357
Employee stock options		1,342		1,985	1,527	2,139
Restricted stock units and other contingently issuable shares		835		3,062	893	3,362
Number of shares used in per share computation		343,914		343,520	343,214	342,872
Continuing operations (in dollars per share)		$ 5.73		$ 4.25	$ 15.77	$ 14.44
Discontinued operations (in dollars per share)		0.00		(0.27)	0.00	(0.66)
Net income per share - diluted (in dollars per share)		$ 5.73		$ 3.98	$ 15.77	$ 13.78
Class A Common Stock | Continuing Operations
Numerator
Reallocation of undistributed earnings as a result of conversion of Class B to Class A shares		$ 298		$ 236	$ 831	$ 813
Reallocation of undistributed earnings		(10)		(2)	(24)	(5)
Allocation of undistributed earnings		1,971		1,460	5,411	4,950
Class A Common Stock | Discontinued operations
Numerator
Reallocation of undistributed earnings as a result of conversion of Class B to Class A shares		0		(15)	0	(37)
Reallocation of undistributed earnings		0		1	0	0
Allocation of undistributed earnings		0		(92)	0	(225)
Class B Common Stock
Numerator
Less: Adjustment Payment to Class C capital stockholders					0	0
Allocation of undistributed earnings - continuing operations		298		236	831	813
Allocation of undistributed earnings - discontinued operations		0		(15)	0	(37)
Net income		$ 298		$ 221	$ 831	$ 776
Denominator
Number of shares used in basic computation		51,369		54,623	52,108	55,357
Continuing operations (in dollars per share)		$ 5.80		$ 4.32	$ 15.95	$ 14.69
Discontinued operations (in dollars per share)		0.00		(0.27)	0.00	(0.67)
Net income per share - basic (in dollars per share)		$ 5.80		$ 4.05	$ 15.95	$ 14.02
Numerator
Adjustment Payment to Class C capital stockholders					$ 0	$ 0
Allocation of undistributed earnings - continuing operations		$ 298		$ 236	831	813
Allocation of undistributed earnings - discontinued operations		$ 0		$ (15)	$ 0	$ (37)
Denominator
Number of shares used in basic computation		51,369		54,623	52,108	55,357
Weighted-average effect of dilutive securities
Conversion of Class B to Class A common shares outstanding		0		0	0	0
Employee stock options		0		0	0	0
Restricted stock units and other contingently issuable shares		0		0	0	0
Number of shares used in per share computation		51,369		54,623	52,108	55,357
Continuing operations (in dollars per share)		$ 5.73		$ 4.25	$ 15.77	$ 14.44
Discontinued operations (in dollars per share)		0.00		(0.27)	0.00	(0.66)
Net income per share - diluted (in dollars per share)		$ 5.73		$ 3.98	$ 15.77	$ 13.78
Class B Common Stock | Continuing Operations
Numerator
Reallocation of undistributed earnings as a result of conversion of Class B to Class A shares		$ 0		$ 0	$ 0	$ 0
Reallocation of undistributed earnings		(4)		(4)	(9)	(14)
Allocation of undistributed earnings		294		232	822	799
Class B Common Stock | Discontinued operations
Numerator
Reallocation of undistributed earnings as a result of conversion of Class B to Class A shares		0		0	0	0
Reallocation of undistributed earnings		0		0	0	1
Allocation of undistributed earnings		0		(15)	0	(36)
Class C Capital Stock
Numerator
Less: Adjustment Payment to Class C capital stockholders					522	0
Allocation of undistributed earnings - continuing operations		1,998		1,462	5,468	4,957
Allocation of undistributed earnings - discontinued operations		0		(92)	0	(226)
Net income		$ 1,998		$ 1,370	$ 5,990	$ 4,731
Denominator
Number of shares used in basic computation		344,698		338,624	342,862	337,562
Continuing operations (in dollars per share)		$ 5.80		$ 4.32	$ 17.47	$ 14.69
Discontinued operations (in dollars per share)		0.00		(0.27)	0.00	(0.67)
Net income per share - basic (in dollars per share)		$ 5.80		$ 4.05	$ 17.47	$ 14.02
Numerator
Adjustment Payment to Class C capital stockholders					$ 522	$ 0
Allocation of undistributed earnings - continuing operations		$ 1,998		$ 1,462	5,468	4,957
Allocation of undistributed earnings - discontinued operations		$ 0		$ (92)	$ 0	$ (226)
Denominator
Number of shares used in basic computation		344,698		338,624	342,862	337,562
Weighted-average effect of dilutive securities
Conversion of Class B to Class A common shares outstanding		0		0	0	0
Employee stock options		1,300		1,962	1,484	2,127
Restricted stock units and other contingently issuable shares		4,407		4,109	4,005	4,036
Number of shares used in per share computation		350,405		344,695	348,351	343,725
Continuing operations (in dollars per share)		$ 5.73		$ 4.25	$ 17.27	$ 14.44
Discontinued operations (in dollars per share)		0.00		(0.27)	0.00	(0.66)
Net income per share - diluted (in dollars per share)		$ 5.73		$ 3.98	$ 17.27	$ 13.78
Stock issued in connection with the Adjustment Payment to Class C Capital stockholders (shares)	853
Adjustment Payment to Class C capital stockholders	$ 47
Class C Capital Stock | Continuing Operations
Numerator
Reallocation of undistributed earnings as a result of conversion of Class B to Class A shares		$ 0		$ 0	$ 0	$ 0
Reallocation of undistributed earnings		10		2	24	5
Allocation of undistributed earnings		2,008		1,464	5,492	4,962
Class C Capital Stock | Discontinued operations
Numerator
Reallocation of undistributed earnings as a result of conversion of Class B to Class A shares		0		0	0	0
Reallocation of undistributed earnings		0		(1)	0	0
Allocation of undistributed earnings		$ 0		$ (93)	$ 0	$ (226)