Accounting Changes - Credit Losses (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Accounting Changes
Deferred tax assets	$ 9,241	$ 5,182
Retained earnings	$ 162,717	162,954
Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjustment
Accounting Changes
Allowance for credit losses		81
Deferred tax assets		(14)
Retained earnings		$ (66)

Amount of allowance for credit loss of accounts and financing receivables. Includes, but is not limited to, notes and loan receivable.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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