Stock Based Awards and Other Equity Instruments - Summary of RSU Activity (Details) (Restricted Stock Units, USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014
Restricted Stock Units
RSUs outstanding
Unvested RSUs outstanding, Beginning balance	1,135,000
Unvested RSUs, Granted	752,000
Unvested RSUs, Vested and released	(307,000)	[1]
Unvested RSUs, Cancelled	(132,000)
Unvested RSUs outstanding, Ending balance	1,448,000
Weighted Average Grant-Date Fair Value Per Share
Unvested RSUs outstanding, Weighted Average Grant-Date Fair Value Per Share, Beginning balance	$ 49.64
Weighted Average Grant-Date Fair Value Per Share, Granted	$ 93.36
Weighted Average Grant-Date Fair Value Per Share, Vested and released	$ 46.78	[1]
Weighted Average Grant-Date Fair Value Per Share, Cancelled	$ 67.50
Unvested RSUs outstanding, Weighted Average Grant-Date Fair Value Per Share, Ending balance	$ 71.33
Aggregate Intrinsic Value
Unvested RSUs outstanding, Aggregate Intrinsic Value	$ 108

[1] Inclusive of 103,641 RSUs withheld to satisfy employee minimum tax withholding 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 consolidated statements of cash flows.