Income Taxes (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Statutory rate	21.00%
Income subject to tonnage tax	(9.70%)
U.S. federal income tax statutory changes	(106.00%)
Non-deductible expenses	3.30%
Noncontrolling interests	0.10%
Foreign earnings not subject to U.S. income tax	0.30%
Foreign taxes not creditable against U.S. income tax	2.90%
Subpart F income	4.80%
State taxes	3.50%
Share award plans	1.80%
Effective income tax rate	(78.00%)	15.10%
Coronavirus Aid, Relief, and Economic Security Act, NOL Carryback, Income Tax Benefit	$ 12.7
Other Receivables
Income Taxes Receivable	$ 34.2

Coronavirus Aid, Relief, and Economic Security Act, NOL Carryback, Income Tax Benefit

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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, Percent

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Effective Income Tax Rate Reconciliation, Subpart F Income, Percent

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Effective Income Tax Rate Reconciliation, U.S. Federal Income Tax Statutory Changes, 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 noncontrolling interest income (loss) exempt from income taxes.

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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).

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Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

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