Loan and lease acquired with deteriorated credit quality [Abstract]

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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
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-Publisher FASB
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-SubTopic 30
-Section 50
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-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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- References

No definition available.

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Amount of direct write-downs of financing receivables charged against the allowance.

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

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- Definition

Amount after allowance and 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 and loans held for sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
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Allowance for Loan and Lease Losses (Summary of Activity In Allowance for Loan and Lease Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Allowance for Loans and Leases Evaluated for Impairment [Abstract]
Net loans and leases			$ 25,235,010	$ 25,299,564
Loan and Leases Acquired with Deteriorated Credit Quality [Abstract]
Loans and leases acquired with deteriorated credit quality			557,356	606,576	$ 703,837	$ 762,998
Commercial
Loan and Leases Acquired with Deteriorated Credit Quality [Abstract]
Loans and leases acquired with deteriorated credit quality			269,913	296,672
Noncommercial
Loan and Leases Acquired with Deteriorated Credit Quality [Abstract]
Loans and leases acquired with deteriorated credit quality			287,443
Noncommercial \| Mortgage
Loan and Leases Acquired with Deteriorated Credit Quality [Abstract]
Loans and leases acquired with deteriorated credit quality				309,904
Non-PCI Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 214,568	$ 211,867
Provision for Loan, Lease, and Other Losses	11,914	5,251
Charge-offs	(10,154)	(9,613)
Recoveries	3,467	3,315
Ending balance	219,795	210,820
Allowance for Loans and Leases Evaluated for Impairment [Abstract]
Loans and leases individually evaluated for impairment			150,001	146,430
Loans and leases collectively evaluated for impairment			24,756,428	24,770,270
Net loans and leases			24,906,429	24,916,700
ALLL for loans and leases individually evaluated for impairment			11,965	9,827
ALLL for loans and leases collectively evaluated for impairment			207,830	204,741
Total allowance for loan and lease losses	214,568	211,867	219,795	214,568	210,820	211,867
Non-PCI Loans \| Commercial \| Construction and land development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	35,270	24,470
Provision for Loan, Lease, and Other Losses	2,119	2,225
Charge-offs	(44)	0
Recoveries	131	23
Ending balance	37,476	26,718
Allowance for Loans and Leases Evaluated for Impairment [Abstract]
Loans and leases individually evaluated for impairment			2,123	2,175
Loans and leases collectively evaluated for impairment			802,340	755,679
Net loans and leases			804,463	757,854
ALLL for loans and leases individually evaluated for impairment			533	490
ALLL for loans and leases collectively evaluated for impairment			36,943	34,780
Total allowance for loan and lease losses	35,270	24,470	37,476	35,270	26,718	24,470
Non-PCI Loans \| Commercial \| Mortgage
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	43,451	45,005
Provision for Loan, Lease, and Other Losses	2,371	(1,365)
Charge-offs	(761)	(46)
Recoveries	220	239
Ending balance	45,281	43,833
Allowance for Loans and Leases Evaluated for Impairment [Abstract]
Loans and leases individually evaluated for impairment			56,157	55,447
Loans and leases collectively evaluated for impairment			10,691,558	10,661,787
Net loans and leases			10,747,715	10,717,234
ALLL for loans and leases individually evaluated for impairment			2,949	2,671
ALLL for loans and leases collectively evaluated for impairment			42,332	40,780
Total allowance for loan and lease losses	43,451	45,005	45,281	43,451	43,833	45,005
Non-PCI Loans \| Commercial \| Other commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,481	4,571
Provision for Loan, Lease, and Other Losses	(83)	(1,293)
Charge-offs	0	0
Recoveries	1	145
Ending balance	2,399	3,423
Allowance for Loans and Leases Evaluated for Impairment [Abstract]
Loans and leases individually evaluated for impairment			541	860
Loans and leases collectively evaluated for impairment			426,878	426,125
Net loans and leases			427,419	426,985
ALLL for loans and leases individually evaluated for impairment			16	42
ALLL for loans and leases collectively evaluated for impairment			2,383	2,439
Total allowance for loan and lease losses	2,481	4,571	2,399	2,481	3,423	4,571
Non-PCI Loans \| Commercial \| Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	55,620	59,824
Provision for Loan, Lease, and Other Losses	2,725	562
Charge-offs	(1,858)	(2,329)
Recoveries	538	1,260
Ending balance	57,025	59,317
Allowance for Loans and Leases Evaluated for Impairment [Abstract]
Loans and leases individually evaluated for impairment			9,987	9,868
Loans and leases collectively evaluated for impairment			3,869,588	3,928,862
Net loans and leases			3,879,575	3,938,730
ALLL for loans and leases individually evaluated for impairment			1,420	1,137
ALLL for loans and leases collectively evaluated for impairment			55,605	54,483
Total allowance for loan and lease losses	55,620	59,824	57,025	55,620	59,317	59,824
Non-PCI Loans \| Commercial \| Other
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,221	4,689
Provision for Loan, Lease, and Other Losses	(498)	114
Charge-offs	0	(3)
Recoveries	444	42
Ending balance	2,167	4,842
Allowance for Loans and Leases Evaluated for Impairment [Abstract]
Loans and leases individually evaluated for impairment			337	291
Loans and leases collectively evaluated for impairment			280,511	296,133
Net loans and leases			280,848	296,424
ALLL for loans and leases individually evaluated for impairment			151	105
ALLL for loans and leases collectively evaluated for impairment			2,016	2,116
Total allowance for loan and lease losses	2,221	4,689	2,167	2,221	4,842	4,689
Non-PCI Loans \| Noncommercial \| Construction and land development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,350	3,962
Provision for Loan, Lease, and Other Losses	123	107
Charge-offs	0	(182)
Recoveries	0	26
Ending balance	2,473	3,913
Allowance for Loans and Leases Evaluated for Impairment [Abstract]
Loans and leases individually evaluated for impairment			3,742	3,749
Loans and leases collectively evaluated for impairment			255,217	253,281
Net loans and leases			258,959	257,030
ALLL for loans and leases individually evaluated for impairment			99	81
ALLL for loans and leases collectively evaluated for impairment			2,374	2,269
Total allowance for loan and lease losses	2,350	3,962	2,473	2,350	3,913	3,962
Non-PCI Loans \| Noncommercial \| Mortgage
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	15,472	15,706
Provision for Loan, Lease, and Other Losses	1,508	1,512
Charge-offs	(166)	(806)
Recoveries	173	77
Ending balance	16,987	16,489
Allowance for Loans and Leases Evaluated for Impairment [Abstract]
Loans and leases individually evaluated for impairment			44,944	42,168
Loans and leases collectively evaluated for impairment			4,258,193	4,223,519
Net loans and leases			4,303,137	4,265,687
ALLL for loans and leases individually evaluated for impairment			3,149	1,901
ALLL for loans and leases collectively evaluated for impairment			13,838	13,571
Total allowance for loan and lease losses	15,472	15,706	16,987	15,472	16,489	15,706
Non-PCI Loans \| Noncommercial \| Revolving mortgage
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	21,862	22,436
Provision for Loan, Lease, and Other Losses	209	466
Charge-offs	(963)	(992)
Recoveries	387	194
Ending balance	21,495	22,104
Allowance for Loans and Leases Evaluated for Impairment [Abstract]
Loans and leases individually evaluated for impairment			29,216	28,852
Loans and leases collectively evaluated for impairment			2,440,682	2,514,123
Net loans and leases			2,469,898	2,542,975
ALLL for loans and leases individually evaluated for impairment			2,742	2,515
ALLL for loans and leases collectively evaluated for impairment			18,753	19,347
Total allowance for loan and lease losses	21,862	22,436	21,495	21,862	22,104	22,436
Non-PCI Loans \| Noncommercial \| Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	35,841	31,204
Provision for Loan, Lease, and Other Losses	3,440	2,923
Charge-offs	(6,362)	(5,255)
Recoveries	1,573	1,309
Ending balance	34,492	30,181
Allowance for Loans and Leases Evaluated for Impairment [Abstract]
Loans and leases individually evaluated for impairment			2,954	3,020
Loans and leases collectively evaluated for impairment			1,731,461	1,710,761
Net loans and leases			1,734,415	1,713,781
ALLL for loans and leases individually evaluated for impairment			906	885
ALLL for loans and leases collectively evaluated for impairment			33,586	34,956
Total allowance for loan and lease losses	35,841	31,204	34,492	35,841	30,181	31,204
PCI Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	9,144	10,026
Provision for Loan, Lease, and Other Losses	(164)	2,354
Charge-offs	0	(84)
Recoveries	0	0
Ending balance	8,980	12,296
Allowance for Loans and Leases Evaluated for Impairment [Abstract]
Total allowance for loan and lease losses	$ 9,144	$ 10,026	8,980	$ 9,144	$ 12,296	$ 10,026
Loan and Leases Acquired with Deteriorated Credit Quality [Abstract]
Loans and leases acquired with deteriorated credit quality			$ 557,356