Amounts Outstanding for Loans and Leases by Segment and Class (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Commercial
Commercial Real Estate	$ 3,848.8	$ 3,333.3
Lease Financing, net	544.4	916.3
Personal
Residential Real Estate	8,900.0	9,800.0
Total Loans and Leases	33,180.9	31,640.2
Allowance for Credit Losses Assigned to Loans and Leases	(193.8)	(267.0)	$ (278.1)
Net Loans and Leases	32,987.1	31,373.2
Commercial
Commercial
Commercial and Institutional	9,431.5	8,381.9
Commercial Real Estate	3,848.8	3,333.3
Lease Financing, net	544.4	916.3
Non-U.S.	1,137.7	1,530.6
Other	194.1	191.5
Personal
Total Loans and Leases	15,156.5	14,353.6
Allowance for Credit Losses Assigned to Loans and Leases	(86.3)	(143.8)	(140.9)
Personal
Commercial
Other	37.3	37.1
Personal
Residential Real Estate	8,850.7	9,782.6
Private Client	9,136.4	7,466.9
Total Loans and Leases	18,024.4	17,286.6
Allowance for Credit Losses Assigned to Loans and Leases	$ (107.5)	$ (123.2)	$ (137.2)

Loans and Leases Receivable, Private Client

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Loans and Leases Receivable, Residential, Real Estate

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Amount before allowance of commercial leases and leveraged lease transactions where the entity is long-term creditor. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes leases covered under loss sharing agreements.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 7
-Subparagraph a, b
-Article 9

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Reflects the net carrying amount of foreign loans and leases held in portfolio, after deducting deferred income, but before deducting the allowance for losses on foreign loans and leases.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount before allowance of other loans and leases not otherwise specified in the taxonomy. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance of loans issued to agricultural, commercial and industrial, and financial institutions. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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Amount before allowance of commercial loans issued to businesses to acquire, develop, construct, improve, or refinance land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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