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Loan To Value Ratio

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Percentage of Exposure to Investment Grade Securities

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Percentage of Financial Institution Exposure Secured

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Purchased residential mortgages.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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

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Loans and asset quality - Credit Risk Indicators Narrative (Details) - USD ($)	6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of exposure to investment grade securities	95.00%
Percentage of financial institution exposure secured	75.00%
Percent of financial institution exposure expiring within one year	90.00%
Loans	$ 55,397,000,000		$ 54,953,000,000
Wealth management loans and mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan to value ratio at origination (percent)	62.00%
Percentage of past due mortgages (less than)	1.00%
Wealth management loans and mortgages \| California
Accounts, Notes, Loans and Financing Receivable [Line Items]
Geographic concentrations (percent)	23.00%
Wealth management loans and mortgages \| New York
Accounts, Notes, Loans and Financing Receivable [Line Items]
Geographic concentrations (percent)	17.00%
Wealth management loans and mortgages \| Massachusetts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Geographic concentrations (percent)	10.00%
Wealth management loans and mortgages \| Florida
Accounts, Notes, Loans and Financing Receivable [Line Items]
Geographic concentrations (percent)	8.00%
Wealth management loans and mortgages \| Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Geographic concentrations (percent)	42.00%
Other residential mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 450,000,000		494,000,000
Overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans			2,700,000,000
Overdraft repayment period	2 days
Margin loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 12,900,000,000		13,400,000,000
Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	42,893,000,000		42,548,000,000
Domestic \| Wealth management loans and mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	15,753,000,000		16,050,000,000
Domestic \| Other residential mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	450,000,000		494,000,000
Purchased mortgages	81,000,000
Domestic \| Overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,073,000,000		524,000,000
Domestic \| Margin loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 11,476,000,000		$ 11,907,000,000
Domestic \| Margin loans \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Required daily collateral margin (in excess of)	100.00%
Equal to or greater than 60 days past due \| Domestic \| Other residential mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of past due mortgages (less than)	25.00%
Overdrafts \| Overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 4,179,000,000
Operating segments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Federal funds sold and securities purchased under resale agreements, allowance for credit losses	$ 0	$ 18,000,000