Equity (Share-Based Compensation - Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized shares available for issuance under share-based compensation plans, number	6,241,114
Options outstanding, number	187,371
Options exercisable, number	187,371
Options outstanding, weighted average exercise price	$ 53.47
Options exercisable, weighted average exercise price	$ 53.47
Options outstanding, intrinsic value, amount	$ 0
Options exercisable, intrinsic value, amount	$ 0
Options granted, number	0	0	0
Options exercised, number	0	0	0
Options forfeited, number	0
Options expired, number	0
ESPP purchase discount rate	15.00%
ESPP shares purchased by employees	73,999	117,950	68,897
ESPP purchase discount, weighted average fair value	$ 10.06	$ 8.34	$ 6.99
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation, amount	$ 8,000,000
Unrecognized share-based compensation, remaining recognition period	9 months 18 days
Awards granted, weighted average grant date fair value	$ 41.81	$ 35.68	$ 38.81
Awards vested, fair value, amount	$ 15,000,000	$ 10,000,000	$ 6,000,000
Performance Shares Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation, amount	$ 14,000,000
Unrecognized share-based compensation, remaining recognition period	1 year 3 months 18 days
Awards granted, weighted average grant date fair value	$ 41.26	$ 35.84	$ 38.97
Awards vested, fair value, amount	$ 4,000,000	$ 0	$ 0
Performance Shares Units (PSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance factor	150.00%

The percentage of the performance factor for the three year period used for perfomance shares and units.

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- Definition

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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Discount rate from fair value on offering date that participants pay for shares.

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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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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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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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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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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

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

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Per share weighted-average price paid for shares purchased on open market for issuance under share-based payment arrangement.

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- Definition

Number of shares issued under share-based payment arrangement.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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

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