Allocated Share Based Compensation Expense Liability Classified Share-Based Awards

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- Definition

Share-based Compensation Arrangement by Liability Classified Share-based Payment Awards Accelerated Compensation Cost

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

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The cash outflow to reacquire common stock during the period.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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Amount of cash paid to settle liability for award under share-based payment arrangement.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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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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Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 08, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sale of Stock, Price Per Share				$ 15.25
Payments for Repurchase of Common Stock	$ 0	$ 79	$ 0
Share-based Payment Arrangement, Accelerated Cost		35
Stock-based compensation expense		41	36
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value		11	0
Option exercises		0	0
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value		88	23
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Share-based Liabilities Paid		25
Share-based Compensation Arrangement by Liability Classified Share-based Payment Awards Accelerated Compensation Cost		16
Allocated Share Based Compensation Expense Liability Classified Share-Based Awards		$ 16	$ 6