Commitments and Contingent Liabilities- Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2014 LegalMatter		Dec. 31, 2013		Jan. 18, 2008	Aug. 31, 2007
Commitments and Contingencies Disclosure [Line Items]
Lending commitment maturing in less than one year	$ 10,200,000,000
Lending commitment maturing in one to five years	24,200,000,000
Lending commitment maturing over five years	400,000,000
Allowance for lending related commitments	128,000,000		134,000,000
Maximum maturities of prearranged contract for a securities lending transaction (in days)	90 days
Cash collateralization percentage generally required for a securities lending transaction with indemnification against broker default (percent)	102.00%
Securities lending indemnifications, secured amount of collateral	286,000,000,000		252,000,000,000
Securities Lending Indemnifications Joint Venture	65,000,000,000		60,000,000,000
Securities Lending Indemnifications Collateral Joint Venture	68,000,000,000		64,000,000,000
Potential exposure of off-balance sheet credit risks	100,000,000
Loss contingency, aggregate range of reasonable loss	745,000,000
Bank filed a proof of claim on Jan. 18, 2008 in the Chapter 11 bankruptcy of Sentinel Management Group, Inc. (Sentinel), seeking to recover approximate amount loaned to Sentinel					312,000,000	312,000,000
Number of Lawsuits Pending Related to Stanford Matter (legal matters)	5
Number of arbitration claims related to Stanford matter	33
Standby letters of credit
Commitments and Contingencies Disclosure [Line Items]
Off Balance Sheet Credit Risk	6,932,000,000	[1]	6,721,000,000	[1]
SBLCs collateralized with cash and securities	489,000,000		418,000,000
SBLCs expiring within one year	3,900,000,000
SBLCs expiring within one to five years	3,000,000,000
Commercial letters of credit
Commitments and Contingencies Disclosure [Line Items]
Off Balance Sheet Credit Risk	280,000,000		310,000,000
Securities lending indemnifications
Commitments and Contingencies Disclosure [Line Items]
Off Balance Sheet Credit Risk	$ 276,106,000,000	[2]	$ 244,382,000,000	[2]

[1] Net of participations totaling $688 million at March 31, 2014 and $720 million at Dec. 31, 2013.

[2] Excludes the indemnification for securities for which BNY Mellon acts as an agent on behalf of CIBC Mellon clients, which totaled $65 billion at March 31, 2014 and $60 billion at