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Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, excluding the effects of master netting arrangements.

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The amount borrowed by a bank, at the federal funds rate, from another bank to meet its reserve requirements.

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Includes: (1) the amount outstanding of funds lent to other depository institutions, securities brokers, or securities dealers in the form of Federal Funds sold; for example, immediately available funds lent under agreements or contracts that mature in one business day or roll over under a continuing contract, regardless of the nature of the transaction or the collateral involved, excluding overnight lending for commercial and industrial purposes. Also include Federal Funds sold under agreements to resell on a gross basis, excluding (1) sales of term Federal Funds, (2) due bills representing purchases of securities or other assets by the reporting bank that have not yet been delivered and similar instruments, (3) resale agreements that mature in more than one business day involving assets other than securities, and (4) yield maintenance dollar repurchase agreements (Federal Funds Sold) and (2) the dollar amount outstanding of funds lent in the form of security resale agreements regardless of maturity, if the agreement requires the bank to resell the identical security purchased or a security that meets the definition of substantially the same in the case of a dollar roll. Also include purchases of participations in pools of securities, regardless of maturity (Securities Purchased Under Agreements to Re-sell).

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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For an unclassified balance sheet, this item represents investments in debt securities which are categorized as held-to-maturity. The held-to-maturity category is for those securities that the entity has the positive intent and ability to hold until maturity.

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The aggregate carrying amount of loans receivable that will be sold to other entities. Includes mortgage and all other loans (collectively, loans) not classified as held for investment. Such loans are stated at the lower of cost or market, or elected fair value. Mortgage loans exclude mortgage-backed securities which are considered a debt security (other loan).

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Book and Fair Values of Financial Instruments (Detail) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010	Dec. 31, 2009
Assets
Cash and Due from Banks	$ 5,099.1	$ 2,818.0	$ 3,524.2	$ 2,491.8
Federal Funds Sold and Resell Agreements	46.6	160.1
Interest-Bearing Deposits with Banks	16,613.8	15,351.3
Federal Reserve Deposits and Other Interest-Bearing	15,173.8	10,924.6
Securities
Available for Sale	24,163.0	19,901.9
Held to Maturity	854.9	922.2
Trading Account	8.3	6.8
Loans (excluding Leases)
Client Security Settlement Receivables	1,577.9	701.3
Deposits
Savings Certificates, Other Time and Non U. S. Offices Interest-Bearing	3,749.1	3,913.0
Federal Funds Purchased	1,103.4	3,691.7
Securities Sold under Agreements to Repurchase	1,479.3	954.4
Other Borrowings	2,281.6	347.7
Senior Notes	1,889.9	1,896.1
Carrying (Reported) Amount, Fair Value Disclosure
Assets
Cash and Due from Banks	5,099.1	2,818.0
Federal Funds Sold and Resell Agreements	46.6	160.1
Interest-Bearing Deposits with Banks	16,613.8	15,351.3
Federal Reserve Deposits and Other Interest-Bearing	15,173.8	10,924.6
Securities
Available for Sale	24,163.0	19,901.9
Held to Maturity	854.9	922.2
Trading Account	8.3	6.8
Loans (excluding Leases)
Held for Investment	27,232.2	26,747.8
Held for Sale	1.5	2.2
Client Security Settlement Receivables	1,577.9	701.3
Other Assets
Federal Reserve and Federal Home Loan Bank Stock	189.6	185.5
Affordable Housing Investments	263.6	265.4
Deposits
Demand, Noninterest-Bearing, and Savings and Money Market	30,925.3	24,810.3
Savings Certificates, Other Time and Non U. S. Offices Interest-Bearing	46,575.6	39,385.4
Federal Funds Purchased	1,103.4	3,691.7
Securities Sold under Agreements to Repurchase	1,479.3	954.4
Other Borrowings	2,281.6	347.7
Senior Notes	1,889.9	1,896.1
Long Term Debt (excluding Leases)
Subordinated Debt	1,018.3	1,148.7
Federal Home Loan Bank Borrowings	1,366.3	1,532.5
Floating Rate Capital Debt	276.9	276.9
Financial Guarantees	55.2	58.6
Loan Commitments	32.5	32.4
Carrying (Reported) Amount, Fair Value Disclosure \| Asset And Liability Management \| Foreign Exchange Contracts
Derivative Instruments
Assets	40.5	44.9
Liabilities	47.0	51.4
Carrying (Reported) Amount, Fair Value Disclosure \| Asset And Liability Management \| Interest Rate Swap Contracts
Derivative Instruments
Assets	131.4	134.6
Liabilities	25.0	15.3
Carrying (Reported) Amount, Fair Value Disclosure \| Asset And Liability Management \| Credit Default Swap Contracts
Derivative Instruments
Liabilities	2.2	2.8
Carrying (Reported) Amount, Fair Value Disclosure \| Asset And Liability Management \| Forward Contracts
Derivative Instruments
Assets	0.1	0.5
Liabilities		0.2
Carrying (Reported) Amount, Fair Value Disclosure \| Client Related and Trading \| Foreign Exchange Contracts
Derivative Instruments
Assets	4,247.8	5,747.9
Liabilities	4,215.3	5,729.9
Carrying (Reported) Amount, Fair Value Disclosure \| Client Related and Trading \| Interest Rate Swap Contracts
Derivative Instruments
Assets	151.3	151.2
Liabilities	147.8	148.4
Carrying (Reported) Amount, Fair Value Disclosure \| Client Related and Trading \| Interest Rate Option Contracts
Derivative Instruments
Assets	0.1	0.1
Liabilities	0.1	0.1
Estimate of Fair Value, Fair Value Disclosure
Assets
Cash and Due from Banks	5,099.1	2,818.0
Federal Funds Sold and Resell Agreements	46.6	160.1
Interest-Bearing Deposits with Banks	16,613.8	15,351.3
Federal Reserve Deposits and Other Interest-Bearing	15,173.8	10,924.6
Securities
Available for Sale	24,163.0	19,901.9
Held to Maturity	872.9	941.8
Trading Account	8.3	6.8
Loans (excluding Leases)
Held for Investment	27,371.3	26,814.2
Held for Sale	1.5	2.2
Client Security Settlement Receivables	1,577.9	701.3
Other Assets
Federal Reserve and Federal Home Loan Bank Stock	189.6	185.5
Affordable Housing Investments	263.6	265.4
Deposits
Demand, Noninterest-Bearing, and Savings and Money Market	30,925.3	24,810.3
Savings Certificates, Other Time and Non U. S. Offices Interest-Bearing	46,242.5	39,402.1
Federal Funds Purchased	1,103.4	3,691.7
Securities Sold under Agreements to Repurchase	1,479.3	954.4
Other Borrowings	2,281.6	347.7
Senior Notes	1,932.3	1,936.5
Long Term Debt (excluding Leases)
Subordinated Debt	1,043.9	1,177.2
Federal Home Loan Bank Borrowings	1,403.6	1,613.5
Floating Rate Capital Debt	239.6	223.2
Financial Guarantees	55.2	58.6
Loan Commitments	32.5	32.4
Estimate of Fair Value, Fair Value Disclosure \| Asset And Liability Management \| Foreign Exchange Contracts
Derivative Instruments
Assets	40.5	44.9
Liabilities	47.0	51.4
Estimate of Fair Value, Fair Value Disclosure \| Asset And Liability Management \| Interest Rate Swap Contracts
Derivative Instruments
Assets	131.4	134.6
Liabilities	25.0	15.3
Estimate of Fair Value, Fair Value Disclosure \| Asset And Liability Management \| Credit Default Swap Contracts
Derivative Instruments
Liabilities	2.2	2.8
Estimate of Fair Value, Fair Value Disclosure \| Asset And Liability Management \| Forward Contracts
Derivative Instruments
Assets	0.1	0.5
Liabilities		0.2
Estimate of Fair Value, Fair Value Disclosure \| Client Related and Trading \| Foreign Exchange Contracts
Derivative Instruments
Assets	4,247.8	5,747.9
Liabilities	4,215.3	5,729.9
Estimate of Fair Value, Fair Value Disclosure \| Client Related and Trading \| Interest Rate Swap Contracts
Derivative Instruments
Assets	151.3	151.2
Liabilities	147.8	148.4
Estimate of Fair Value, Fair Value Disclosure \| Client Related and Trading \| Interest Rate Option Contracts
Derivative Instruments
Assets	0.1	0.1
Liabilities	$ 0.1	$ 0.1