Loans and Leases - Loan and Lease Balances (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Loans and Leases Receivable Disclosure
Loans and leases	$ 36,221,019	$ 34,466,408
Loan and lease adjustments	(85,400)	(118,600)
Commercial
Loans and Leases Receivable Disclosure
Loans and leases	25,694,668	23,942,201
Commercial \| Commercial and industrial
Loans and Leases Receivable Disclosure
Loans and leases	12,856,701	11,422,383
Commercial \| Commercial and industrial \| PPP Loan
Loans and Leases Receivable Disclosure
Loans and leases	1,900,000	1,600,000
Commercial \| Commercial real estate
Loans and Leases Receivable Disclosure
Loans and leases	9,881,341	9,702,587
Commercial \| Lease financing
Loans and Leases Receivable Disclosure
Loans and leases	2,956,626	2,817,231
Consumer
Loans and Leases Receivable Disclosure
Loans and leases	10,526,351	10,524,207
Consumer \| Residential mortgage
Loans and Leases Receivable Disclosure
Loans and leases	6,510,981	6,182,045
Consumer \| Home equity
Loans and Leases Receivable Disclosure
Loans and leases	2,864,142	3,108,736
Consumer \| Consumer installment
Loans and Leases Receivable Disclosure
Loans and leases	$ 1,151,228	$ 1,233,426

Amount, after allowance for credit loss and unamortized deferred fee, premium, and discount, of financing receivable covered under loss sharing agreement and financing receivable not covered under loss sharing agreement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

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+ References

No definition available.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

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