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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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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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Book and Fair Values of Financial Instruments (Detail) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010	Dec. 31, 2009
Assets
Cash and Due from Banks	$ 4,336.6	$ 2,818.0	$ 3,489.5	$ 2,491.8
Federal Funds Sold and Resell Agreements	221.8	160.1
Interest-Bearing Deposits with Banks	18,944.2	15,351.3
Federal Reserve Deposits and Other Interest-Bearing	6,498.2	10,924.6
Securities
Available for Sale	28,439.3	19,901.9
Held to Maturity	829.2	922.2
Trading Account	6.3	6.8
Loans (excluding Leases)
Client Security Settlement Receivables	948.2	701.3
Deposits
Savings Certificates, Other Time and Non U. S. Offices Interest-Bearing	3,529.4	3,913.0
Federal Funds Purchased	737.8	3,691.7
Securities Sold under Agreements to Repurchase	339.3	954.4
Other Borrowings	817.6	347.7
Senior Notes	2,133.5	1,896.1
Carrying (Reported) Amount, Fair Value Disclosure
Assets
Cash and Due from Banks	4,336.6	2,818.0
Federal Funds Sold and Resell Agreements	221.8	160.1
Interest-Bearing Deposits with Banks	18,944.2	15,351.3
Federal Reserve Deposits and Other Interest-Bearing	6,498.2	10,924.6
Securities
Available for Sale	28,439.3	19,901.9
Held to Maturity	829.2	922.2
Trading Account	6.3	6.8
Loans (excluding Leases)
Held for Investment	27,369.6	26,747.8
Held for Sale	10.0	2.2
Client Security Settlement Receivables	948.2	701.3
Other Assets
Federal Reserve and Federal Home Loan Bank Stock	185.3	185.5
Affordable Housing Investments	252.3	265.4
Deposits
Demand, Noninterest-Bearing, and Savings and Money Market	37,401.0	24,810.3
Savings Certificates, Other Time and Non U. S. Offices Interest-Bearing	41,113.0	39,385.4
Federal Funds Purchased	737.8	3,691.7
Securities Sold under Agreements to Repurchase	339.3	954.4
Other Borrowings	817.6	347.7
Senior Notes	2,133.5	1,896.1
Long Term Debt (excluding Leases)
Subordinated Debt	1,036.6	1,148.7
Federal Home Loan Bank Borrowings	1,055.0	1,532.5
Floating Rate Capital Debt	276.9	276.9
Financial Guarantees	102.2	58.6
Loan Commitments	32.8	32.4
Carrying (Reported) Amount, Fair Value Disclosure \| Asset And Liability Management \| Foreign Exchange Contracts
Derivative Instruments
Assets	23.7	44.9
Liabilities	26.8	51.4
Carrying (Reported) Amount, Fair Value Disclosure \| Asset And Liability Management \| Interest Rate Swap Contracts
Derivative Instruments
Assets	154.4	134.6
Liabilities	42.8	15.3
Carrying (Reported) Amount, Fair Value Disclosure \| Asset And Liability Management \| Credit Default Swap Contracts
Derivative Instruments
Liabilities	0.4	2.8
Carrying (Reported) Amount, Fair Value Disclosure \| Asset And Liability Management \| Forward Contracts
Derivative Instruments
Assets		0.5
Liabilities		0.2
Carrying (Reported) Amount, Fair Value Disclosure \| Client Related and Trading \| Foreign Exchange Contracts
Derivative Instruments
Assets	5,202.9	5,747.9
Liabilities	5,190.0	5,729.9
Carrying (Reported) Amount, Fair Value Disclosure \| Client Related and Trading \| Interest Rate Swap Contracts
Derivative Instruments
Assets	193.6	151.2
Liabilities	189.5	148.4
Carrying (Reported) Amount, Fair Value Disclosure \| Client Related and Trading \| Interest Rate Option Contracts
Derivative Instruments
Assets		0.1
Liabilities		0.1
Estimate of Fair Value, Fair Value Disclosure
Assets
Cash and Due from Banks	4,336.6	2,818.0
Federal Funds Sold and Resell Agreements	221.8	160.1
Interest-Bearing Deposits with Banks	18,944.2	15,351.3
Federal Reserve Deposits and Other Interest-Bearing	6,498.2	10,924.6
Securities
Available for Sale	28,439.3	19,901.9
Held to Maturity	847.2	941.8
Trading Account	6.3	6.8
Loans (excluding Leases)
Held for Investment	27,603.0	26,814.2
Held for Sale	10.0	2.2
Client Security Settlement Receivables	948.2	701.3
Other Assets
Federal Reserve and Federal Home Loan Bank Stock	185.3	185.5
Affordable Housing Investments	252.3	265.4
Deposits
Demand, Noninterest-Bearing, and Savings and Money Market	37,401.0	24,810.3
Savings Certificates, Other Time and Non U. S. Offices Interest-Bearing	41,126.0	39,402.1
Federal Funds Purchased	737.8	3,691.7
Securities Sold under Agreements to Repurchase	339.3	954.4
Other Borrowings	817.6	347.7
Senior Notes	2,196.1	1,936.5
Long Term Debt (excluding Leases)
Subordinated Debt	1,038.9	1,177.2
Federal Home Loan Bank Borrowings	1,101.9	1,613.5
Floating Rate Capital Debt	229.9	223.2
Financial Guarantees	102.2	58.6
Loan Commitments	32.8	32.4
Estimate of Fair Value, Fair Value Disclosure \| Asset And Liability Management \| Foreign Exchange Contracts
Derivative Instruments
Assets	23.7	44.9
Liabilities	26.8	51.4
Estimate of Fair Value, Fair Value Disclosure \| Asset And Liability Management \| Interest Rate Swap Contracts
Derivative Instruments
Assets	154.4	134.6
Liabilities	42.8	15.3
Estimate of Fair Value, Fair Value Disclosure \| Asset And Liability Management \| Credit Default Swap Contracts
Derivative Instruments
Liabilities	0.4	2.8
Estimate of Fair Value, Fair Value Disclosure \| Asset And Liability Management \| Forward Contracts
Derivative Instruments
Assets		0.5
Liabilities		0.2
Estimate of Fair Value, Fair Value Disclosure \| Client Related and Trading \| Foreign Exchange Contracts
Derivative Instruments
Assets	5,202.9	5,747.9
Liabilities	5,190.0	5,729.9
Estimate of Fair Value, Fair Value Disclosure \| Client Related and Trading \| Interest Rate Swap Contracts
Derivative Instruments
Assets	193.6	151.2
Liabilities	189.5	148.4
Estimate of Fair Value, Fair Value Disclosure \| Client Related and Trading \| Interest Rate Option Contracts
Derivative Instruments
Assets		0.1
Liabilities		$ 0.1