Loans and Leases (Loans and Leases Outstanding) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Loans and Leases Receivable, Gross, Carrying Amount, Covered	$ 84,800	$ 272,600
PCI Loans	809,169	950,516	$ 1,186,498
Non-PCI	20,928,709	19,289,474
Total loans and leases	21,737,878	20,239,990
Commercial
PCI Loans	499,970	593,614
Non-PCI	13,760,703	12,630,489
Commercial \| Construction and land development
PCI Loans	20,766	33,880
Non-PCI	649,157	620,352
Commercial \| Mortgage
PCI Loans	453,013	525,468
Non-PCI	9,026,220	8,274,548
Commercial \| Commercial and industrial
PCI Loans	11,844	15,182
Non-PCI	2,567,501	2,368,958
Commercial \| Lease financing
Non-PCI	826,270	730,778
Commercial \| Other commercial real estate
PCI Loans	12,645	17,076
Non-PCI	351,291	321,021
Commercial \| Other
PCI Loans	1,702	2,008
Non-PCI	340,264	314,832
Noncommercial
PCI Loans	309,199	356,902
Non-PCI	7,168,006	6,658,985
Noncommercial \| Construction and land development
Non-PCI	231,400	220,073
Noncommercial \| Mortgage
Non-PCI	2,889,124	2,695,985
Noncommercial \| Revolving mortgage
Non-PCI	2,601,344	2,523,106
Noncommercial \| Consumer
PCI Loans	1,772	2,273
Non-PCI	$ 1,446,138	$ 1,219,821

All loans and leases, excluding purchased-credit impaired loans accounted for under ASC 310-30.

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- Definition

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and other-than-temporary impairments), for loans accounted for as debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

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- Definition

Aggregate gross carrying amount of loans and leases receivable covered by loss sharing agreements.

+ References

No definition available.

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