Nonperforming Assets (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012		Dec. 31, 2011
Financing Receivable, Impaired [Line Items]
Nonperforming loans	$ 318		$ 329
Other assets owned	13		12
Total nonperforming assets	331	[1]	341	[1]
Domestic | Other Residential Mortgages
Financing Receivable, Impaired [Line Items]
Nonperforming loans	188		203
Domestic | Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Nonperforming loans	39		40
Domestic | Wealth Management Loans and Mortgages
Financing Receivable, Impaired [Line Items]
Nonperforming loans	35		32
Domestic | Commercial
Financing Receivable, Impaired [Line Items]
Nonperforming loans	32		21
Domestic | Financial Institutions
Financing Receivable, Impaired [Line Items]
Nonperforming loans	14		23
Foreign
Financing Receivable, Impaired [Line Items]
Nonperforming loans	$ 10		$ 10

[1] Loans of consolidated investment management funds are not part of BNY Mellon's loan portfolio. Included in these loans are nonperforming loans of $180 million at March 31, 2012 and $101 million at Dec. 31, 2011. These loans are recorded at fair value and therefore do not impact the provision for credit losses and allowance for loan losses, and accordingly are excluded from the nonperforming assets table above.