Income tax benefits associated with exercise settlement of stock based awards.

No definition available.

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- Definition

Calculation price based on the average stock price of the last ten trading days.

+ References

No definition available.

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- Definition

End of requisite service period for share based compensation arrangement.

+ References

No definition available.

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- Definition

Share-based compensation arrangement by share-based payment award target payment.

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Amount of cost capitalized for award under share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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.

+ References

No definition available.

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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

Description of modification of award under share-based payment arrangement. Includes, but is not limited to, terms for expiration date, vesting rights and exercise price.

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Stock Based Awards and Other Equity Instruments - Additional Information (Details)			3 Months Ended		6 Months Ended
	May 27, 2020	May 08, 2020 USD ($) TradingDay	Jun. 30, 2020 USD ($) $ / shares	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) $ / shares	Jun. 30, 2019 USD ($)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Capitalized stock based compensation as internal-use software and website development costs			$ 4,000,000	$ 5,000,000	$ 8,000,000	$ 9,000,000
Number of Average Trading Days \| TradingDay		10
Total stock-based compensation expense			25,000,000	32,000,000	51,000,000	60,000,000
Income tax benefits from exercise or settlement of stock-based awards			$ 1,000,000	$ 3,000,000	$ 13,000,000	22,000,000
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Target payment		$ 7,000,000
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Closing stock price \| $ / shares			$ 19.01		$ 19.01
Total intrinsic value					$ 2,000,000	2,000,000
Total fair value of stock options vested					$ 11,000,000	$ 10,000,000
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense			$ 10,000,000
Stock award modification term					On May 27, 2020, the Compensation Committee of the Board of Directors, approved a modification to the Company’s annual RSU grant issued to its employees in the first quarter of 2020, which consisted of reducing the original grant-date vesting period from four years to two years.
Restricted Stock Units \| Maximum \| Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Term of stock options, grant-date vesting period	4 years
Restricted Stock Units \| Minimum [Member] \| Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Term of stock options, grant-date vesting period	2 years
MSUs \| Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Requisite service period for estimated grant-date fair value of stock awards					Dec. 31, 2022