Income Taxes - Significant Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Accrued expenses	$ 189	$ 303
Share-based compensation	185	216
Net operating loss and credit carry-forwards	1,158	1,444
Foreign tax credits on undistributed earnings	0	289
Leasing liabilities	171	219
Other	76	65
Subtotal	1,779	2,536
Valuation allowance	(888)	(1,145)
Total deferred tax assets	891	1,391
Capitalized software development costs	(614)	(622)
Intangible assets	(2,993)	(3,297)
Property and equipment	(198)	(143)
Capitalized commissions	(87)	(86)
Investments in joint ventures	(908)	(841)
Leasing right-of-use assets	(141)	(205)
Other	(311)	(332)
Total deferred tax liabilities	(5,252)	(5,526)
Total	$ (4,361)	$ (4,135)

Deferred Tax Assets, Leasing Liabilities

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Deferred Tax Assets, Tax Credits On Undistributed Foreign Earnings

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Deferred Tax Liabilities, Deferred Expense, Capitalized Commissions

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount of deferred tax liability attributable to taxable temporary differences from investments (excludes investments in subsidiaries and equity method investments).

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