Aggregate number of common shares reserved for future issuance.

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Number of common shares issuable upon conversion for each share of preferred stock to be converted.

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Number of common shares issuable upon conversion of preferred stock.

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

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

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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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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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Stock Transactions and Stock-based Compensation (Narrative) (Details) $ / shares in Units, $ in Millions			3 Months Ended	12 Months Ended
	Apr. 15, 2022 $ / shares shares	Apr. 01, 2022 USD ($) shares	Apr. 01, 2022 USD ($) d shares	Dec. 31, 2021	Jul. 16, 2013 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized shares to be repurchased					20,000,000
Remaining number of shares authorized to be repurchased		20,000,000	20,000,000
Common shares reserved for issuance under the 2007 Omnibus Incentive Plan, shares		44,000,000	44,000,000
RSU/PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost \| $		$ 353	$ 353
Weighted average period for cost to be recognized		2 years
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost \| $		$ 340	$ 340
Weighted average period for cost to be recognized		2 years
Common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Threshold consecutive trading days \| d			20
Conversion of stock, shares converted			1,196
Preferred stock \| Preferred stock series A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion of stock, shares converted			180
Preferred stock, dividend rate, percent			4.75%	4.75%
Preferred stock \| Preferred stock series A \| Subsequent event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, dividend rate, percent	4.75%
Preferred stock, convertible, conversion rate	6.6632
Preferred stock, convertible, shares issuable	11,000,000
Dividends paid (in usd per share) \| $ / shares	$ 11.875