Stock Based Awards and Other Equity Instruments - Summary of RSU Activity (Details) - Restricted Stock Units $ / shares in Units, shares in Thousands, $ in Millions	9 Months Ended
	Sep. 30, 2016 USD ($) $ / shares shares
RSUs outstanding
Unvested RSUs outstanding, Beginning balance | shares	1,750
Unvested RSUs, Granted | shares	1,887
Unvested RSUs, Vested and released | shares	(492)	[1]
Unvested RSUs, Cancelled or expired | shares	(217)
Unvested RSUs outstanding, Ending balance | shares	2,928
Weighted Average Grant-Date Fair Value Per Share
Unvested RSUs outstanding, Weighted Average Grant-Date Fair Value Per Share, Beginning balance | $ / shares	$ 79.02
Weighted Average Grant-Date Fair Value Per Share, Granted | $ / shares	63.96
Weighted Average Grant-Date Fair Value Per Share, Vested and released | $ / shares	74.12	[1]
Weighted Average Grant-Date Fair Value Per Share, Cancelled or expired | $ / shares	73.60
Unvested RSUs outstanding, Weighted Average Grant-Date Fair Value Per Share, Ending balance | $ / shares	$ 70.52
Aggregate Intrinsic Value
Unvested RSUs outstanding, Aggregate Intrinsic Value | $	$ 185

[1] Inclusive of 140,873 RSUs withheld to satisfy employee withholding tax requirements due to net share settlement. Potential shares which had been convertible under RSUs that were withheld under net share settlement remain in the authorized but unissued pool under the 2011 Plan and can be reissued by the Company. Total payments for the employees’ tax obligations to the taxing authorities due to net share settlements are reflected as a financing activity within the unaudited condensed consolidated statements of cash flows.