Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Equity [Abstract]
Repurchase of common stock, shares	0	0	4,707,450	0
Aggregate cost of shares repurchased, common stock			$ 115
Average price of shares repurchased, common stock			$ 24.32
Remaining authorized share repurchased amount	$ 75		$ 75		$ 190
Treasury stock, shares	18,844,614		18,844,614		14,116,534
Aggregate cost of treasury stock	$ 722		$ 722		$ 607

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Amount remaining of a stock repurchase plan authorized.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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Number of shares that have been repurchased during the period and are being held in treasury.

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The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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