Number of Loans and Leases Modified in TDRs and Total Recorded Investments and Unpaid Principal Balances (Detail) - Lease Financing, net $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($) Contract	Dec. 31, 2015 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Loans or leases modified in trouble debt restructuring \| Contract	89	136
Troubled debt restructurings, recorded investment	$ 37.3	$ 54.9
Troubled debt restructurings, unpaid principal balance	$ 43.1	$ 62.9
Commercial
Financing Receivable, Modifications [Line Items]
Loans or leases modified in trouble debt restructuring \| Contract	14	7
Troubled debt restructurings, recorded investment	$ 13.0	$ 26.4
Troubled debt restructurings, unpaid principal balance	$ 17.5	$ 28.1
Commercial \| Commercial and Institutional
Financing Receivable, Modifications [Line Items]
Loans or leases modified in trouble debt restructuring \| Contract	7	3
Troubled debt restructurings, recorded investment	$ 4.3	$ 24.6
Troubled debt restructurings, unpaid principal balance	$ 6.5	$ 26.1
Commercial \| Real Estate
Financing Receivable, Modifications [Line Items]
Loans or leases modified in trouble debt restructuring \| Contract	7	4
Troubled debt restructurings, recorded investment	$ 8.7	$ 1.8
Troubled debt restructurings, unpaid principal balance	$ 11.0	$ 2.0
Personal
Financing Receivable, Modifications [Line Items]
Loans or leases modified in trouble debt restructuring \| Contract	75	129
Troubled debt restructurings, recorded investment	$ 24.3	$ 28.5
Troubled debt restructurings, unpaid principal balance	$ 25.6	$ 34.8
Personal \| Real Estate
Financing Receivable, Modifications [Line Items]
Loans or leases modified in trouble debt restructuring \| Contract	73	128
Troubled debt restructurings, recorded investment	$ 22.2	$ 27.9
Troubled debt restructurings, unpaid principal balance	$ 23.5	$ 34.2
Personal \| Private Client
Financing Receivable, Modifications [Line Items]
Loans or leases modified in trouble debt restructuring \| Contract	2	1
Troubled debt restructurings, recorded investment	$ 2.1	$ 0.6
Troubled debt restructurings, unpaid principal balance	$ 2.1	$ 0.6

Financing Receivable, Modifications, Recorded Investment, Modified During Period

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Financing Receivable, Modifications, Unpaid Principal Balance

+ References

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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