Class Of Warrant Or Right, Stated Interest Rate

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- Definition

Fair market value of common stock, Percentage.

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Share based compensation arrangement by share based payment award maximum amount per employee.

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Terminated, Number

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Unrecognized compensation forfeited rate.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of warrants or rights outstanding.

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- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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The number of warrants issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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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 aggregate amount paid by the entity to reacquire the right to purchase equity shares at a predetermined price, usually issued together with corporate debt.

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Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

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- Definition

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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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

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The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

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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- Definition

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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- Definition

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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- Definition

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

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Number of shares for which recognition of compensation cost was accelerated.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Stockholders' Equity - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended			12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants issued (in shares)									13,490,236
Striking price of Warrants (USD per share)									$ 53.8475
Cash paid for partial termination of 1.125% Warrants						$ 549,000,000	$ 0	$ 0
Unrecognized compensation expense			$ 35,000,000			$ 35,000,000
Unrecognized compensation forfeited rate						16.10%
Weighted average grant date fair value of stock options granted (usd per share)						$ 41.43
Granted (in shares)						0		0
Common stock issued during period (in shares)						216,000	351,000	410,000
Separation Costs - Former Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restructuring settled without cash							$ 23,000,000
RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period of unrecognized compensation expense						2 years 7 months
Accelerating vesting awards (in shares)							133,957
PSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period of unrecognized compensation expense						2 months
Accelerating vesting awards (in shares)							153,574
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period of unrecognized compensation expense						2 years
Accelerating vesting awards (in shares)							139,272
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense			$ 9,000,000			$ 9,000,000
Weighted average period of unrecognized compensation expense						1 year 9 months
Risk free interest rate						2.30%
Expected volatility rate						38.40%
Dividend yield						0.00%
Expected term of awards						8 years 5 months
Options exercised, intrinsic value							$ 2,000,000	$ 1,000,000
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)			3,000,000			3,000,000
Dividend yield						0.00%
Expected term of awards						6 months 4 days
Employee purchase price as a percentage of stock price						85.00%
Maximum annual contribution per employee						$ 25,000
Risk-free interest rate, minimum						0.40%
Risk-free interest rate, maximum						1.90%
Minimum expected volatility rate inputs for fair value measurement						31.00%
Maximum expected volatility rate inputs for fair value measurement						44.00%
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation (in shares)						365,000	857,000
2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)			4,500,000.0			4,500,000.0
2011 Plan \| RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum award vesting period						4 years
2011 Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum award vesting period						4 years
Stock option expiration period						10 years
1.625% Convertible Notes \| Convertible Debt
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Convertible debt, shares converted in transaction (in shares)	1,800,000	2,600,000		600,000
1.125% Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stated interest rate			1.125%			1.125%
Class of warrant			6,200,000			6,200,000
Cash paid for partial termination of 1.125% Warrants			$ 130,000,000	$ 306,000,000	$ 113,000,000
Options terminated (in shares)			1,500,000	3,400,000	2,400,000