Loans and Leases - Loan and Lease Balances (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Loans and Leases Receivable Disclosure
Loans and leases	$ 33,510,752	$ 19,073,020
Loan and lease adjustments	(234,400)	(1,500)
Commercial
Loans and Leases Receivable Disclosure
Loans and leases	22,281,686	11,659,108
Commercial \| Commercial and industrial
Loans and Leases Receivable Disclosure
Loans and leases	10,810,534	6,220,632
Commercial \| Commercial real estate
Loans and Leases Receivable Disclosure
Loans and leases	8,876,779	2,908,313
Commercial \| Lease financing
Loans and Leases Receivable Disclosure
Loans and leases	2,594,373	2,530,163
Consumer
Loans and Leases Receivable Disclosure
Loans and leases	11,229,066	7,413,912
Consumer \| Residential mortgage
Loans and Leases Receivable Disclosure
Loans and leases	6,057,404	2,335,835
Consumer \| Consumer installment
Loans and Leases Receivable Disclosure
Loans and leases	1,562,252	2,003,572
Consumer \| Home equity
Loans and Leases Receivable Disclosure
Loans and leases	$ 3,609,410	$ 3,074,505

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524

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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

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-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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