Loans and Leases (Loans and Leases Outstanding) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Loans and leases, not acquired in a transfer accounted for as debt securities	$ 32,033,898	$ 32,329,093
PCI Loans	337,624	462,882
Total loans and leases	32,371,522	32,791,975
Commercial
Loans and leases, not acquired in a transfer accounted for as debt securities	22,280,288	22,558,060
Commercial \| Construction and land development
Loans and leases, not acquired in a transfer accounted for as debt securities	1,111,797	985,424
Commercial \| Commercial and industrial
Loans and leases, not acquired in a transfer accounted for as debt securities	5,710,652	5,013,644
Commercial \| Mortgage Receivable, Owner Occupied
Loans and leases, not acquired in a transfer accounted for as debt securities	11,992,625	11,165,012
Commercial \| Mortgage Receivable, Non-Owner Occupied
Loans and leases, not acquired in a transfer accounted for as debt securities	2,971,393	2,987,689
Commercial \| SBA-PPP
Loans and leases, not acquired in a transfer accounted for as debt securities	493,821	2,406,291
Consumer Portfolio Segment
Loans and leases, not acquired in a transfer accounted for as debt securities	9,753,610	9,771,033
Consumer Portfolio Segment \| Construction and land development
Loans and leases, not acquired in a transfer accounted for as debt securities	399,570	348,123
Consumer Portfolio Segment \| Residential Mortgage
Loans and leases, not acquired in a transfer accounted for as debt securities	5,679,919	5,561,686
Consumer Portfolio Segment \| Revolving Mortgage
Loans and leases, not acquired in a transfer accounted for as debt securities	1,795,005	2,052,854
Consumer Portfolio Segment \| Consumer Auto Loan
Loans and leases, not acquired in a transfer accounted for as debt securities	1,331,388	1,255,402
Consumer Portfolio Segment \| Consumer Loan, Other
Loans and leases, not acquired in a transfer accounted for as debt securities	$ 547,728	$ 552,968

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://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=123409700&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=124259787&loc=d3e4428-111522

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