Share Based Compensation (Share Based Compensation Plans) (Details)	6 Months Ended
Jun. 30, 2018 shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Director stock awards granted	1,625,000
Employee Stock Purchase Plan shares issued	27,117,000
Restricted stock awards granted	121,850,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Stock Options, Outstanding as of December 31, 2017	1,546,014,000
Stock Option, Granted	78,775,000
Stock Option, Exercised	(133,437,000)
Stock Options, Outstanding as of June 30, 2018	1,491,352,000
Shares available for future grants and ESPP purchases as of June 30,2018	966,898,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	300,000

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Number of share options (or share units) exercised during the current period.

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