Income Taxes (U.S. Federal Statutory Rate) (Details)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
U.S. Federal statutory rate	21.00%	21.00%	21.00%
U.S. state and local income taxes—net of U.S. Federal income tax benefit	2.30%	2.50%	3.00%
Differences related to non-U.S. operations	0.10%	2.30%	3.00%
U.K. statutory rate change	2.60%	0.00%	0.00%
Gain on consolidation of business	(1.50%)	0.00%	0.00%
Equity compensation	(0.70%)	(1.40%)	(1.30%)
Uncertain tax positions	0.10%	1.10%	0.00%
Other	0.70%	1.20%	1.60%
Effective tax rate	24.60%	26.70%	27.30%

Effective Income Tax Rate Reconciliation, Gain On Deconsolidation Of Business, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

+ References

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for share-based payment arrangement.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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