Loans and Leases (Loans and Leases Outstanding) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Loans and Leases Receivable, Gross, Carrying Amount, Covered	$ 272,600	$ 485,300
PCI Loans	950,516	1,186,498	$ 1,029,426
Non-PCI	19,289,474	17,582,967
Total loans and leases	20,239,990	18,769,465
Commercial
PCI Loans	593,614	726,123
Non-PCI	12,630,489	11,205,639
Commercial \| Construction and land development
PCI Loans	33,880	78,079
Non-PCI	620,352	493,133
Commercial \| Mortgage
PCI Loans	525,468	577,518
Non-PCI	8,274,548	7,552,948
Commercial \| Commercial and industrial
PCI Loans	15,182	27,254
Non-PCI	2,368,958	1,988,934
Commercial \| Lease financing
Non-PCI	730,778	571,916
Commercial \| Other commercial real estate
PCI Loans	17,076	40,193
Non-PCI	321,021	244,875
Commercial \| Other
PCI Loans	2,008	3,079
Non-PCI	314,832	353,833
Noncommercial
PCI Loans	356,902	460,375
Non-PCI	6,658,985	6,377,328
Noncommercial \| Construction and land development
PCI Loans	0	912
Non-PCI	220,073	205,016
Noncommercial \| Mortgage
PCI Loans	302,158	382,340
Non-PCI	2,695,985	2,493,058
Noncommercial \| Revolving mortgage
PCI Loans	52,471	74,109
Non-PCI	2,523,106	2,561,800
Noncommercial \| Consumer
PCI Loans	2,273	3,014
Non-PCI	$ 1,219,821	$ 1,117,454

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=28367877&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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