Loans and Leases - Loan and Lease Balances (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Loans and Leases Receivable Disclosure
Loans and leases	$ 34,466,408	$ 34,497,464
Loan and lease adjustments	(118,600)	(201,500)
Commercial Loan and Lease Portfolio
Loans and Leases Receivable Disclosure
Loans and leases	23,942,201	23,276,341
Commercial Loan and Lease Portfolio \| Commercial and industrial
Loans and Leases Receivable Disclosure
Loans and leases	11,422,383	11,439,602
Commercial Loan and Lease Portfolio \| Commercial and industrial \| PPP Loan
Loans and Leases Receivable Disclosure
Loans and leases	1,600,000
Commercial Loan and Lease Portfolio \| Commercial real estate
Loans and Leases Receivable Disclosure
Loans and leases	9,702,587	9,136,870
Commercial Loan and Lease Portfolio \| Lease financing
Loans and Leases Receivable Disclosure
Loans and leases	2,817,231	2,699,869
Consumer
Loans and Leases Receivable Disclosure
Loans and leases	10,524,207	11,221,123
Consumer \| Residential mortgage
Loans and Leases Receivable Disclosure
Loans and leases	6,182,045	6,179,805
Consumer \| Home equity
Loans and Leases Receivable Disclosure
Loans and leases	3,108,736	3,498,907
Consumer \| Consumer installment
Loans and Leases Receivable Disclosure
Loans and leases	$ 1,233,426	$ 1,542,411

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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