v3.20.4

Income Taxes (Schedule Of Effective Income Tax Rate) (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Statutory rate	21.00%	21.00%	21.00%
Income subject to tonnage tax	(7.30%)	(2.30%)	(1.30%)
U.S. federal income tax statutory changes	(49.10%)	0.00%	0.00%
Non-deductible expenses	3.40%	1.60%	0.20%
Noncontrolling interests	0.00%	(3.10%)	(5.70%)
Foreign earnings not subject to U.S. income tax	(4.80%)	(4.10%)	(16.20%)
Foreign taxes not creditable against U.S. income tax	0.20%	1.40%	3.20%
Subpart F income	3.00%	1.50%	12.10%
State taxes	5.90%	2.00%	(3.10%)
Share award plans	1.60%	0.60%	(0.30%)
Other	(0.90%)	1.40%	(0.70%)
Effective income tax rate	(27.00%)	20.00%	9.20%

Effective Income Tax Rate Reconciliation, Foreign Taxes Not Creditable In U.S., Percent

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Effective Income Tax Rate Reconciliation, Income Subject To Tonnage Tax, Percent

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Effective Income Tax Rate Reconciliation, Nondeductible Expense, Excluding Share-based Compensation Expense

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Effective Income Tax Rate Reconciliation, Subpart F Income, Percent

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

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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 attributable to changes in the income tax rates.

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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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