Common shares unissued but encumbered.

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Treasury Stock, Shares, Acquired, Additional Shares Received

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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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Aggregate dividends paid during the period for each share of common stock outstanding.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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The percentage rate used to calculate dividend payments on preferred stock.

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The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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

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Amount of stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and are being held in 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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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the par value method.

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Stockholders' Equity - Additional Information (Details) - USD ($)				12 Months Ended
	Feb. 02, 2021	Jan. 28, 2021	Mar. 10, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 27, 2021	Nov. 30, 2020	Oct. 31, 2020	Jan. 22, 2020	Jan. 23, 2019
Class of Stock [Line Items]
Common stock, shares authorized (in shares)				1,125,000,000	1,125,000,000
Common stock, shares issued (in shares)				456,700,000	453,600,000
Common stock, aggregate purchase price				$ 91,346,000	$ 90,720,000
Common stock, par value (in dollars per share)				$ 0.20	$ 0.20
Common stock dividend per common share				$ 0.12	$ 0.12
Common stock dividends						$ 0
Common stock repurchased (in shares)			44,900,000	47,736,847	16,962,199	0
Repurchase amount (in dollars per share)				$ 75,000,000
2020 Share Repurchase Program
Class of Stock [Line Items]
Aggregate purchase price (not to exceed)										$ 600,000,000
Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock shares outstanding (in shares)				2,500,000	4,000,000
Preferred stock liquidation preference (in dollars per share)				$ 100
Common stock, shares authorized (in shares)									2,000,000
Common stock, shares issued (in shares)								1,489,304
Common stock, aggregate purchase price								$ 68,000,000
Common stock, par value (in dollars per share)								$ 45
Series B Preferred Stock \| Three Month LIBOR
Class of Stock [Line Items]
Preferred stock dividend rate (as a percentage)				170.00%
Common Stock
Class of Stock [Line Items]
Common stock, shares authorized (in shares)				1,125,000,000
Common stock, par value (in dollars per share)				$ 0.20
Common stock shares outstanding (in shares)				375,000,000
Common shares unissued but encumbered (in shares)				35,000,000
Share price (in dollars per share)				$ 12.39
Common Stock \| 2019 Share Repurchase Program
Class of Stock [Line Items]
Aggregate purchase price (not to exceed)											$ 200,000,000
Common stock repurchased (in shares)				3,000,000	17,000,000
Repurchase amount (in dollars per share)				$ 33,000,000	$ 167,000,000
Common Stock \| 2020 Share Repurchase Program
Class of Stock [Line Items]
Common stock repurchased (in shares)			44,900,000
Payment for delivery of common stock			$ 525,000,000
Common Stock \| Subsequent Event \| 2020 Share Repurchase Program
Class of Stock [Line Items]
Common stock repurchased (in shares)		58,000,000
Repurchase amount (in dollars per share)		$ 9.01
Additional shares repurchased		13,000,000
Common Stock \| Subsequent Event \| 2021 Share Repurchase Program
Class of Stock [Line Items]
Aggregate purchase price (not to exceed)							$ 1,250,000,000
Common Stock \| Subsequent Event \| Tender Offer
Class of Stock [Line Items]
Common stock, par value (in dollars per share)	$ 0.20
Aggregate purchase price (not to exceed)	$ 1,000,000,000
Common Stock \| Subsequent Event \| Tender Offer \| Maximum
Class of Stock [Line Items]
Repurchase amount (in dollars per share)	15.00
Common Stock \| Subsequent Event \| Tender Offer \| Minimum
Class of Stock [Line Items]
Repurchase amount (in dollars per share)	$ 13.10