Stock Based Awards and Other Equity Instruments - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Capitalized stock based compensation as internal-use software and website development costs	$ 3	$ 4
Income tax benefits from exercise or settlement of stock-based awards	$ 9	12
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Closing stock price	$ 53.79
Total intrinsic value	$ 8
Term of stock options, granted	10 years
Stock options vest period	4 years
Total fair value of stock options vested	$ 8	$ 8
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options vest period	4 years

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

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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.

+ References

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-Publisher FASB
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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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

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.

+ References

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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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