Additional common shares reserved for issuance as a percentage of common stock outstanding

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Net stock options as a percentage of outstanding shares at beginning of period

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Share-based Compensation Arrangement by Share-based Payment Award, Exercisable Period After Termination

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Share-based compensation arrangement by share-based payment award, maximum number of shares per employee value

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Share-based compensation arrangement by share-based payment award, maximum shares authorized for purchase by employees

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Share-based compensation arrangement by share-based payment award, numerator in fixing the shares authorized for purchase

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Share-Based Compensation Arrangement By Share Based Payment Award, Options Pre-Vesting Forfeitures Estimated

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Share-based compensation arrangement by share-based payment award, period of terms

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Share-based Compensation Arrangement by Share-based Payment Award, Exercisable Period After Termination in Case of Death or Disability

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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Aggregate number of common shares reserved for future issuance.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The cash inflow associated with the amount received from holders to acquire the entity's shares under incentive and share awards other than stock option exercises. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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No definition available.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Discount rate from fair value on offering date that participants pay for shares.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Share-Based Compensation (Narrative) (Details) - USD ($)				12 Months Ended			120 Months Ended
	May 20, 2015	May 15, 2012	Feb. 17, 2000	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Feb. 17, 2010	May 31, 2013	Mar. 23, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Intrinsic value of stock options exercised				$ 6,800,000
Cash received from exercise of stock options				14,900,000	$ 27,100,000	$ 24,900,000
Proceeds from issuance of common stock under the ESPP				$ 15,000,000	$ 14,600,000	$ 10,000,000
Number of Shares, Granted (in shares)				0	0	0
Pre-vesting forfeitures (as a percent)				11.00%	11.00%	11.00%
Period after termination in which options can be exercised (in days)		90 days
Period after termination in which options can be exercised in case of death or disability (in years)		1 year
Number of options vested and expected to vest (in shares)				3,300,000
Weighted average exercise price of options vested and expected to vest (in dollars per share)				$ 7.75
Net stock options as a percentage of outstanding shares at beginning of period				(0.01%)	(0.02%)
Share-based compensation expense before income taxes				$ 56,100,000	$ 46,900,000	$ 45,800,000
2000 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved and available for grant (in shares)							30,500,000
Additional common shares reserved for issuance as a percentage of common stock outstanding							3.00%
Term of grant agreement (in years)		10 years
Amended And Restated Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance under the plan (in shares)		59,100,000							33,000,000
Term of grant agreement (in years)		7 years
Aggregate of common stock available for grant (in shares)				19,800,000
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash received from exercise of stock options				$ 14,900,000
Proceeds from issuance of common stock under the ESPP				15,000,000
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense on non-vested stock awards				$ 100,000
Recognition period for compensation expense (in years)				7 months 6 days
Employee Stock Option [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)		3 years
Employee Stock Option [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)		4 years
Time Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense on non-vested stock awards				$ 61,300,000
Compensation expense recognized on restricted stock units				$ 31,700,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognition period for compensation expense (in years)				1 year 9 months 18 days
Aggregate of common stock available for grant (in shares)				4,900,000
Restricted Stock [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards granted in period (in shares)				200,000
Weighted average grant date fair value (In dollars per share)				$ 9.81
Share-based compensation expense before income taxes				$ 1,800,000
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate of common stock available for grant (in shares)	23,500,000							18,000,000
Maximum employee subscription rate for the ESPP (as a percent)			10.00%
Discount rate from market value paid by participants for shares under the plan (as a percent)			85.00%
Maximum annual amount of purchases per employee under the plan			$ 25,000
Shares authorized for purchase per employee per quarter (in shares)			500
Maximum fair value of shares employee may purchase in a quarter			$ 6,250
Shares issued pursuant to the employee stock purchase plan (in shares)				1,800,000	1,700,000	1,300,000
Increase in number of shares available for grant	5,500,000
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense on non-vested stock awards				$ 45,200,000
Pre-vesting forfeitures (as a percent)				5.00%	5.00%	5.00%
Equity awards granted in period (in shares)				6,200,000
Compensation expense recognized on restricted stock units				$ 49,400,000
Weighted average grant date fair value (In dollars per share)				$ 9.50
Restricted Stock Units [Member] \| Officers And Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards granted in period (in shares)				2,000,000
Restricted Stock Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)		3 years
Performance Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense on non-vested stock awards				$ 16,100,000