Loans and Leases (Nonaccrual) (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	$ 109,927	$ 167,960
Total Past Due and Non-accrual	40,704	89,433
Interest on non-accrual loans that would have been recorded as additional interest income	11,000	9,700	$ 11,300
Commercial Portfolio Segment [Member]
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	70,467	95,197
Total Past Due and Non-accrual	11,198	35,497
Commercial Portfolio Segment [Member] \| Non-Real Estate Receivables [Member]
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	59,607	64,073
Total Past Due and Non-accrual	4,802	16,985
Commercial Portfolio Segment [Member] \| Asset Based Lending [Member]
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	2,086	2,594
Total Past Due and Non-accrual	2,086	0
Commercial Portfolio Segment [Member] \| Commercial Real Estate [Member]
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	5,046	21,231
Total Past Due and Non-accrual	4,310	15,529
Commercial Portfolio Segment [Member] \| 6172 Finance Lessors [Member]
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	3,728	7,299
Total Past Due and Non-accrual	0	2,983
Consumer Portfolio Segment [Member]
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	39,460	72,763
Total Past Due and Non-accrual	29,506	53,936
Consumer Portfolio Segment [Member] \| Residential Mortgage [Member]
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	15,747	41,081
Total Past Due and Non-accrual	10,584	29,843
Consumer Portfolio Segment [Member] \| Home Equity Loan [Member]
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	23,489	31,030
Total Past Due and Non-accrual	18,920	24,091
Consumer Portfolio Segment [Member] \| 522291 Consumer Lending [Member]
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	224	652
Total Past Due and Non-accrual	$ 2	$ 2

Amount of financing receivable on nonaccrual status with no allowance for credit loss.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (3)

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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