Loans - By Portfolio Segment (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Loan balances by portfolio segment:
Retained loans	$ 948,642	$ 1,003,089	$ 960,506
Held-for-sale	11,898		7,873
At fair value	50,767		44,474
Total	1,011,307		1,012,853
Accrued interest receivables	2,900		2,900
Accrued interest receivables written off	13	14
Consumer, excluding credit card
Loan balances by portfolio segment:
Retained loans	302,392	293,779	302,127
Held-for-sale	1,232		1,305
At fair value	21,284		15,147
Total	324,908		318,579
Credit card
Loan balances by portfolio segment:
Retained loans	131,772		143,432
Held-for-sale	721		784
At fair value	0		0
Total	132,493		144,216
Wholesale
Loan balances by portfolio segment:
Retained loans	514,478	$ 555,289	514,947
Held-for-sale	9,945		5,784
At fair value	29,483		29,327
Total	$ 553,906		$ 550,058

Financing Receivable, Before Allowance For Credit Losses, Net of Deferred Income

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Amount, before allowance for credit loss, of accrued interest on financing receivable.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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Amount, before allowance for credit loss, of financing receivable.

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