Income Taxes - Temporary Tax Effects (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Asset (Liability)
Tax losses and tax credits	$ 334,303	$ 330,839
Operating lease liabilities	358,066	320,261
Bonus and deferred compensation	295,690	280,747
Bad debt and other reserves	73,061	66,504
Pension obligation	18,026	24,022
Investments	17,506	5,236
Tax effect on revenue items related to Topic 606 adoption	(16,784)	(25,620)
Property and equipment	(88,595)	(54,370)
Unconsolidated affiliates and partnerships	(59,544)	(63,594)
Capitalized costs and intangibles	(313,099)	(277,246)
Operating lease assets	(366,671)	(314,433)
All other	6,181
All other		(1,153)
Net deferred tax assets before valuation allowance	258,140	291,193
Valuation allowance	(291,096)	(251,922)
Net deferred tax (liabilities)	$ (32,956)
Net deferred tax assets		$ 39,271

Deferred tax assets and liabilities in unconsolidated affiliates and partnership.

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Deferred tax assets operating lease liabilities.

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Deferred tax liabilities capitalized cost and intangibles.

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Deferred tax liabilities operating lease assets.

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Deferred tax liabilities revenue recognition.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from investments (excludes investments in subsidiaries and equity method investments).

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from employee bonuses.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from pension benefits.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the allowance for doubtful accounts.

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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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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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Amount of deferred tax liability attributable to taxable temporary differences classified as other.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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