Loans and Leases (Borrower Ratings) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Total	$ 33,378.4	$ 31,640.2
1 to 3 Category
Financing Receivable, Recorded Investment [Line Items]
Total	17,865.9	16,322.9
4 to 5 Category
Financing Receivable, Recorded Investment [Line Items]
Total	15,017.4	14,680.4
6 to 9 Category (Watch List)
Financing Receivable, Recorded Investment [Line Items]
Total	495.1	636.9
Commercial
Financing Receivable, Recorded Investment [Line Items]
Commercial and Institutional	9,478.6	8,381.9
Commercial Real Estate	3,814.6	3,333.3
Lease Financing, net	807.2	916.3
Non-U.S.	1,250.2	1,530.6
Other	166.8	191.5
Total	15,517.4	14,353.6
Commercial \| 1 to 3 Category
Financing Receivable, Recorded Investment [Line Items]
Commercial and Institutional	6,472.1	5,340.9
Commercial Real Estate	1,648.0	1,371.7
Lease Financing, net	458.5	552.5
Non-U.S.	435.4	636.8
Other	99.0	108.1
Total	9,113.0	8,010.0
Commercial \| 4 to 5 Category
Financing Receivable, Recorded Investment [Line Items]
Commercial and Institutional	2,932.1	2,947.3
Commercial Real Estate	2,113.5	1,861.8
Lease Financing, net	345.9	360.3
Non-U.S.	814.6	892.9
Other	67.8	83.4
Total	6,273.9	6,145.7
Commercial \| 6 to 9 Category (Watch List)
Financing Receivable, Recorded Investment [Line Items]
Commercial and Institutional	74.4	93.7
Commercial Real Estate	53.1	99.8
Lease Financing, net	2.8	3.5
Non-U.S.	0.2	0.9
Other	0.0	0.0
Total	130.5	197.9
Personal
Financing Receivable, Recorded Investment [Line Items]
Residential Real Estate	9,077.5	9,782.6
Private Client	8,751.3	7,466.9
Other	32.2	37.1
Total	17,861.0	17,286.6
Personal \| 1 to 3 Category
Financing Receivable, Recorded Investment [Line Items]
Residential Real Estate	3,092.5	3,148.0
Private Client	5,641.4	5,143.8
Other	19.0	21.1
Total	8,752.9	8,312.9
Personal \| 4 to 5 Category
Financing Receivable, Recorded Investment [Line Items]
Residential Real Estate	5,631.4	6,207.0
Private Client	3,098.9	2,311.7
Other	13.2	16.0
Total	8,743.5	8,534.7
Personal \| 6 to 9 Category (Watch List)
Financing Receivable, Recorded Investment [Line Items]
Residential Real Estate	353.6	427.6
Private Client	11.0	11.4
Other	0.0	0.0
Total	$ 364.6	$ 439.0

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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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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 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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