Share-based Compensation Plans Shared-based Compensation Plans (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Incentive compensation plan, shares available for future grants of equity-based awards	30,703,972
Share-based compensation, RSUs and PSUs, outstanding, non-vested	4,864,000
Share-based compensation, RSUs and PSUs, outstanding, non-vested, weighted-average grant date fair value per share	$ 23.71
Share-based compensation, RSUs and PSUs, granted	3,007,000
Share-based compensation, RSUs and PSUs, granted, weighted-average grant date fair value per share	$ 26.29
Share-based compensation, RSUs and PSUs, vested	(3,411,000)
Share-based compensation, RSUs and PSUs, vested, weighted-average grant date fair value per share	$ 22.37
Share-based compensation, RSUs and PSUs, forfeited	(93,000)
Share-based compensation, RSUs and PSUs, forfeited, weighted-average grant date fair value per share	$ 26.28
Share-based compensation, RSUs and PSUs, outstanding, non-vested	4,367,000	4,864,000
Share-based compensation, RSUs and PSUs, outstanding, non-vested, weighted-average grant date fair value per share	$ 26.48	$ 23.71
Share-based compensation, expense	$ 67,000,000	$ 72,000,000	$ 60,000,000
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSU awards payable upon vest	0
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSU awards payable upon vest	$ 1.50

PSU awards payable upon vest

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

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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

Net number of non-option equity instruments granted to participants.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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