Loans and Leases (Loans and Leases Outstanding) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Loans and leases, not acquired in a transfer accounted for as debt securities	$ 32,329,093	$ 28,322,780
PCI Loans	462,882	558,716
Total loans and leases	32,791,975	28,881,496
Commercial
Loans and leases, not acquired in a transfer accounted for as debt securities	22,558,060	18,552,002
Commercial \| Construction and land development
Loans and leases, not acquired in a transfer accounted for as debt securities	985,424	1,013,454
Commercial \| Mortgage
Loans and leases, not acquired in a transfer accounted for as debt securities		12,282,635
Commercial \| Commercial and industrial
Loans and leases, not acquired in a transfer accounted for as debt securities	5,013,644	4,403,792
Commercial \| Other commercial real estate
Loans and leases, not acquired in a transfer accounted for as debt securities		542,028
Commercial \| Other
Loans and leases, not acquired in a transfer accounted for as debt securities		310,093
Commercial \| Mortgage Receivable, Owner Occupied
Loans and leases, not acquired in a transfer accounted for as debt securities	11,165,012
Commercial \| Mortgage Receivable, Non-Owner Occupied
Loans and leases, not acquired in a transfer accounted for as debt securities	2,987,689
Commercial \| SBA-PPP
Loans and leases, not acquired in a transfer accounted for as debt securities	2,406,291
Noncommercial
Loans and leases, not acquired in a transfer accounted for as debt securities		9,770,778
Noncommercial \| Construction and land development
Loans and leases, not acquired in a transfer accounted for as debt securities		357,385
Noncommercial \| Mortgage
Loans and leases, not acquired in a transfer accounted for as debt securities		5,293,917
Noncommercial \| Revolving mortgage
Loans and leases, not acquired in a transfer accounted for as debt securities		2,339,072
Noncommercial \| Consumer
Loans and leases, not acquired in a transfer accounted for as debt securities		$ 1,780,404
Consumer Portfolio Segment
Loans and leases, not acquired in a transfer accounted for as debt securities	9,771,033
Consumer Portfolio Segment \| Construction and land development
Loans and leases, not acquired in a transfer accounted for as debt securities	348,123
Consumer Portfolio Segment \| Residential Mortgage
Loans and leases, not acquired in a transfer accounted for as debt securities	5,561,686
Consumer Portfolio Segment \| Revolving Mortgage
Loans and leases, not acquired in a transfer accounted for as debt securities	2,052,854
Consumer Portfolio Segment \| Consumer Auto Loan
Loans and leases, not acquired in a transfer accounted for as debt securities	1,255,402
Consumer Portfolio Segment \| Consumer Loan, Other
Loans and leases, not acquired in a transfer accounted for as debt securities	$ 552,968

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

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121585399&loc=d3e13503-111538

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=121614798&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://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=121593590&loc=d3e4428-111522

+ Details

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