Income tax disclosure.

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Net payable to former parent for spin-off related tax liabilities.

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Offsetting tax benefits to liability for income taxes associated with uncertain tax positions.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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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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Amount 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 expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of other current and other deferred income tax expense (benefit) attributable to continuing operations.

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Other information relative to a tax position which it is reasonably possible that the total amount of the unrecognized tax benefit will significantly increase or decrease within twelve months of the balance sheet date.

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Amount of valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from tax credit carryforwards for which it is more likely than not that a tax benefit will not be realized.

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Amount of unrecognized tax benefits.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Income Taxes (Narrative) (Detail) - USD ($) $ in Thousands	12 Months Ended
Income Taxes (Narrative) (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Line Items]
Income (loss) from continuing operations before noncontrolling interests, Domestic	$ 857,200	$ 571,900	$ 391,400
Income (loss) from continuing operations before noncontrolling interests, Foreign	$ 47,800	$ 37,600	$ 53,900
Federal income tax rates	21.00%	21.00%	35.00%
Effective income tax rates	21.60%	21.90%	5.30%
Tax benefits recorded	$ 3,200	$ 5,200	$ 3,400
Net payable related to spin-off tax liabilities	500	15,600
Foreign tax credit carryover net of valuation allowance	6,500
Operating loss carryforwards, amount	80,200
Operating loss carryforwards, indefinite expiration, amount	31,700
Operating loss carryforwards, subject to expiration, amount	48,500
Deferred tax asset valuation allowance	9,846	10,621
Liability for income taxes associated with uncertain tax positions	1,500	13,300	12,800	$ 18,100
Offsetting tax benefits related to uncertain tax positions	400	3,700	3,700
Accrued interest and penalties on uncertain tax positions	26	5,800	5,300
Other tax benefits related to interest and penalties of uncertain tax positions	$ 26	5,800	$ 5,300
Unrecognized tax positions increase decrease, months	It is reasonably possible that the amount of the unrecognized benefit with respect to certain of the Company’s unrecognized tax positions may increase or decrease within the next 12 months. Any such change may be the result of ongoing audits or the expiration of federal and state statutes of limitations for the assessment of taxes.
Deferred Tax Assets Valuation Allowances On Net Operating Loss Carryforwards
Income Tax Disclosure [Line Items]
Deferred tax asset valuation allowance	$ 8,800	8,900
Deferred Tax Assets Valuation Allowances On Other Deferred Tax Assets
Income Tax Disclosure [Line Items]
Deferred tax asset valuation allowance	1,000	$ 1,700
Federal
Income Tax Disclosure [Line Items]
Operating loss carryforwards, amount	200
State
Income Tax Disclosure [Line Items]
Operating loss carryforwards, amount	35,900
Foreign
Income Tax Disclosure [Line Items]
Operating loss carryforwards, amount	$ 44,100