Other assets - Components of Other Assets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Other Assets [Abstract]
Corporate/bank-owned life insurance	$ 5,219	$ 4,937
Accounts receivable	3,802	3,692
Fails to deliver	1,671	2,274
Software	1,590	1,652
Prepaid pension assets	1,464	1,357
Renewable energy investments	1,144	1,264
Equity in a joint venture and other investments	1,102	1,064
Qualified affordable housing project investments	1,024	999
Prepaid expense	491	385
Federal Reserve Bank stock	466	484
Income taxes receivable	388	1,125
Seed capital	184	224
Fair value of hedging derivatives	21	289
Other	1,655	1,552
Total other assets	20,221	21,298
Federal Home Loan Bank stock, at cost	$ 22	$ 111

Equity in joint ventures and other investments

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Renewable Energy Investments

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Seed Capital investments

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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Amount of investment in qualified affordable housing projects.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Aggregate fair value of all derivative assets designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

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This item represents the amount that could be realized under a life insurance contract or contracts owned by the Entity as of the date of the statement of financial position. Such Entity-owned life insurance policies are commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Amount of assets classified as other.

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Amount of other miscellaneous assets.

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Carrying amount as of the balance sheet date of expenditures made in advance of when the economic benefit of the cost will be realized, and which will be expensed in future periods with the passage of time or when a triggering event occurs.

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Amount receivable from broker-dealers and clearing organizations, including, but not limited to, securities failed-to-deliver, certain deposits for securities borrowed, open transactions, good faith and margin deposits, commissions and floor brokerage receivables.

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