Stock-Based Payments (Stock Option Activity) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding in Shares [Roll Forward]
Number of shares outstanding at December 31 (shares)	1,020
Number of shares exercised	(1,020)
Number of shares cancelled	0
Number of shares outstanding at December 31 (shares)	0	1,020
Number of shares exercisable at December 31 (shares)	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Weighted average exercise price outstanding, beginning	$ 56
Weighted average exercise price exercised	56
Weighted average exercise price cancelled	0
Weighted average exercise price outstanding, ending	0	$ 56
Weighted average exercise price exercisable	$ 0
Weighted average remaining contractual life outstanding	0 years	6 months
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term	0 years
Aggregate intrinsic value outstanding, beginning	$ 0.2
Aggregate intrinsic value outstanding, ending	0.0	$ 0.2
Aggregate intrinsic value exercisable	$ 0.0

Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding in Shares [Roll Forward]

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Number of options outstanding, including both vested and non-vested options.

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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of share options (or share units) exercised during the current period.

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