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Allowance for Loan and Lease Losses (Allocation of Allowance for Loan and Lease Losses) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | $ 1,044,148 | $ 1,199,358 | $ 1,044,148 | $ 1,199,358 |
Allowance for loan and lease losses | 224,865 |  | 224,865 |  | $ 221,893
Loans and Leases Receivable, Net Amount | 24,313,572 |  | 24,313,572 |  | 23,374,932
Non-PCI impaired loans less than $500,000 collectively evaluated | 44,100 |  | 44,100 |  | 49,100
PCI Loans |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Acquired loans which have adverse change in expected cash flows | 160,800 |  | 160,800 |  | 279,800
Provision for Loan, Lease, and Other Losses | 161 | 2,572 | 2,515 | (273) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 34 | 0 | 118 | 0 |
Recoveries | 0 | 0 | 0 | 0 |
Non-PCI Loans |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Total impaired noncovered loans and leases | 155,228 |  | 155,228 |  | 155,646
Unpaid principal balance | 174,460 |  | 174,460 |  | 170,034
Impaired Financing Receivable, Related Allowance | 10,001 |  | 10,001 |  | 9,728
ALLL for loans and leases individually evaluated for impairment | 10,001 |  | 10,001 |  | 9,728
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 83,622 |  | 83,622 |  | 77,199
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 71,606 |  | 71,606 |  | 78,447
Financing Receivable, Individually Evaluated for Impairment | 155,228 |  | 155,228 |  | 155,646
Average balance | 155,051 | 139,608 | 155,038 | 138,144 |
Interest income recognized | 1,370 | 1,179 | 2,742 | 2,327 |
Provision for Loan, Lease, and Other Losses | 8,277 | 9,752 | 13,528 | 20,828 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 9,678 | 9,423 | 19,291 | 18,194 |
Recoveries | 3,023 | 4,954 | 6,338 | 7,642 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 202,441 |  | 202,441 |  | 202,139
Financing Receivable, Collectively Evaluated for Impairment | 23,708,940 |  | 23,708,940 |  | 22,678,181
Loans and Leases Receivable, Net Amount | 23,864,168 |  | 23,864,168 |  | 22,833,827
Non-PCI Loans | Commercial | Construction and land development |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 2,431 |  | 2,431 |  | 1,110
ALLL for loans and leases individually evaluated for impairment | 274 |  | 274 |  | 185
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 2,098 |  | 2,098 |  | 788
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 0 |  | 0 |  | 0
Financing Receivable, Individually Evaluated for Impairment | 2,098 |  | 2,098 |  | 788
Average balance | 1,485 | 970 | 1,320 | 1,013 |
Interest income recognized | 17 | 11 | 28 | 23 |
Provision for Loan, Lease, and Other Losses | (3,139) | 2,372 | (914) | 4,908 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 8 | 413 | 8 | 490 |
Recoveries | 93 | 209 | 116 | 264 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 23,390 |  | 23,390 |  | 24,285
Financing Receivable, Collectively Evaluated for Impairment | 712,913 |  | 712,913 |  | 668,427
Loans and Leases Receivable, Net Amount | 715,011 |  | 715,011 |  | 669,215
Non-PCI Loans | Commercial | Mortgage |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 72,467 |  | 72,467 |  | 78,936
ALLL for loans and leases individually evaluated for impairment | 3,325 |  | 3,325 |  | 3,648
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 35,934 |  | 35,934 |  | 39,135
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 30,238 |  | 30,238 |  | 34,520
Financing Receivable, Individually Evaluated for Impairment | 66,172 |  | 66,172 |  | 73,655
Average balance | 68,113 | 74,121 | 70,190 | 74,715 |
Interest income recognized | 659 | 651 | 1,370 | 1,293 |
Provision for Loan, Lease, and Other Losses | 866 | 639 | (499) | 645 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 459 | 235 | 505 | 272 |
Recoveries | 225 | 731 | 464 | 1,095 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 41,140 |  | 41,140 |  | 41,357
Financing Receivable, Collectively Evaluated for Impairment | 10,212,569 |  | 10,212,569 |  | 9,655,367
Loans and Leases Receivable, Net Amount | 10,278,741 |  | 10,278,741 |  | 9,729,022
Non-PCI Loans | Commercial | Other commercial real estate |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 1,264 |  | 1,264 |  | 2,267
ALLL for loans and leases individually evaluated for impairment | 65 |  | 65 |  | 209
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 375 |  | 375 |  | 1,351
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 702 |  | 702 |  | 506
Financing Receivable, Individually Evaluated for Impairment | 1,077 |  | 1,077 |  | 1,857
Average balance | 1,345 | 1,525 | 1,529 | 1,555 |
Interest income recognized | 12 | 9 | 23 | 17 |
Provision for Loan, Lease, and Other Losses | 468 | 33 | (825) | 337 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 69 | 0 | 69 | 5 |
Recoveries | 1 | 7 | 146 | 11 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 3,758 |  | 3,758 |  | 4,362
Financing Receivable, Collectively Evaluated for Impairment | 472,375 |  | 472,375 |  | 471,576
Loans and Leases Receivable, Net Amount | 473,452 |  | 473,452 |  | 473,433
Non-PCI Loans | Commercial | Commercial and industrial |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 11,684 |  | 11,684 |  | 10,475
ALLL for loans and leases individually evaluated for impairment | 985 |  | 985 |  | 665
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 6,262 |  | 6,262 |  | 6,326
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 1,390 |  | 1,390 |  | 1,648
Financing Receivable, Individually Evaluated for Impairment | 7,652 |  | 7,652 |  | 7,974
Average balance | 7,585 | 10,159 | 7,554 | 10,844 |
Interest income recognized | 76 | 98 | 152 | 202 |
Provision for Loan, Lease, and Other Losses | 5,670 | 968 | 5,245 | 4,560 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 1,994 | 3,121 | 3,469 | 6,374 |
Recoveries | 638 | 2,392 | 1,857 | 2,657 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 56,345 |  | 56,345 |  | 53,032
Financing Receivable, Collectively Evaluated for Impairment | 3,089,889 |  | 3,089,889 |  | 2,722,433
Loans and Leases Receivable, Net Amount | 3,097,541 |  | 3,097,541 |  | 2,730,407
Non-PCI Loans | Commercial | Lease financing |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 2,808 |  | 2,808 |  | 2,571
ALLL for loans and leases individually evaluated for impairment | 107 |  | 107 |  | 397
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 789 |  | 789 |  | 1,890
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 387 |  | 387 |  | 24
Financing Receivable, Individually Evaluated for Impairment | 1,176 |  | 1,176 |  | 1,914
Average balance | 1,842 | 1,911 | 2,040 | 1,740 |
Interest income recognized | 14 | 14 | 25 | 28 |
Provision for Loan, Lease, and Other Losses | (1,879) | 186 | (892) | 761 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 445 | 97 | 1,299 | 270 |
Recoveries | 4 | 0 | 45 | 6 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 3,874 |  | 3,874 |  | 5,730
Financing Receivable, Collectively Evaluated for Impairment | 612,201 |  | 612,201 |  | 892,887
Loans and Leases Receivable, Net Amount | 613,377 |  | 613,377 |  | 894,801
Non-PCI Loans | Commercial | Other |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 315 |  | 315 |  | 521
ALLL for loans and leases individually evaluated for impairment | 20 |  | 20 |  | 0
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 97 |  | 97 |  | 0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 0 |  | 0 |  | 521
Financing Receivable, Individually Evaluated for Impairment | 97 |  | 97 |  | 521
Average balance | 67 | 434 | 34 | 315 |
Interest income recognized | 0 | 5 | 0 | 7 |
Provision for Loan, Lease, and Other Losses | (114) | (214) | 0 | 241 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 38 | 64 | 41 | 187 |
Recoveries | 1 | 46 | 43 | 121 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 4,671 |  | 4,671 |  | 4,689
Financing Receivable, Collectively Evaluated for Impairment | 296,517 |  | 296,517 |  | 301,655
Loans and Leases Receivable, Net Amount | 296,614 |  | 296,614 |  | 302,176
Non-PCI Loans | Noncommercial | Construction and land development |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 3,633 |  | 3,633 |  | 5,224
ALLL for loans and leases individually evaluated for impairment | 66 |  | 66 |  | 68
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 544 |  | 544 |  | 592
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 2,367 |  | 2,367 |  | 3,959
Financing Receivable, Individually Evaluated for Impairment | 2,911 |  | 2,911 |  | 4,551
Average balance | 3,526 | 3,185 | 3,815 | 2,895 |
Interest income recognized | 44 | 33 | 92 | 66 |
Provision for Loan, Lease, and Other Losses | 50 | (10) | 157 | (93) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 37 | 0 | 219 | 0 |
Recoveries | 101 | 0 | 127 | 0 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 3,961 |  | 3,961 |  | 3,894
Financing Receivable, Collectively Evaluated for Impairment | 247,793 |  | 247,793 |  | 243,738
Loans and Leases Receivable, Net Amount | 250,704 |  | 250,704 |  | 248,289
Non-PCI Loans | Noncommercial | Mortgage |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 46,684 |  | 46,684 |  | 39,946
ALLL for loans and leases individually evaluated for impairment | 3,343 |  | 3,343 |  | 2,733
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 25,529 |  | 25,529 |  | 19,135
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 18,424 |  | 18,424 |  | 18,707
Financing Receivable, Individually Evaluated for Impairment | 43,953 |  | 43,953 |  | 37,842
Average balance | 42,046 | 36,767 | 40,385 | 34,864 |
Interest income recognized | 298 | 272 | 573 | 525 |
Provision for Loan, Lease, and Other Losses | 1,492 | 155 | 3,004 | 1,506 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 289 | 222 | 1,095 | 472 |
Recoveries | 110 | 75 | 187 | 362 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 14,459 |  | 14,459 |  | 12,973
Financing Receivable, Collectively Evaluated for Impairment | 3,936,892 |  | 3,936,892 |  | 3,485,944
Loans and Leases Receivable, Net Amount | 3,980,845 |  | 3,980,845 |  | 3,523,786
Non-PCI Loans | Noncommercial | Revolving mortgage |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 30,170 |  | 30,170 |  | 25,941
ALLL for loans and leases individually evaluated for impairment | 1,112 |  | 1,112 |  | 1,085
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 10,217 |  | 10,217 |  | 5,875
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 17,190 |  | 17,190 |  | 17,895
Financing Receivable, Individually Evaluated for Impairment | 27,407 |  | 27,407 |  | 23,770
Average balance | 26,388 | 8,484 | 25,590 | 8,227 |
Interest income recognized | 222 | 62 | 423 | 119 |
Provision for Loan, Lease, and Other Losses | 289 | 1,054 | 755 | 1,604 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 1,027 | 280 | 2,019 | 1,105 |
Recoveries | 520 | 401 | 714 | 953 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 20,774 |  | 20,774 |  | 21,351
Financing Receivable, Collectively Evaluated for Impairment | 2,577,548 |  | 2,577,548 |  | 2,677,755
Loans and Leases Receivable, Net Amount | 2,604,955 |  | 2,604,955 |  | 2,701,525
Non-PCI Loans | Noncommercial | Consumer |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 3,004 |  | 3,004 |  | 3,043
ALLL for loans and leases individually evaluated for impairment | 704 |  | 704 |  | 738
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 1,777 |  | 1,777 |  | 2,107
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 908 |  | 908 |  | 667
Financing Receivable, Individually Evaluated for Impairment | 2,685 |  | 2,685 |  | 2,774
Average balance | 2,654 | 2,052 | 2,581 | 1,976 |
Interest income recognized | 28 | 24 | 56 | 47 |
Provision for Loan, Lease, and Other Losses | 4,574 | 4,569 | 7,497 | 6,359 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 5,312 | 4,991 | 10,567 | 9,019 |
Recoveries | 1,330 | $ 1,093 | 2,639 | $ 2,173 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 30,069 |  | 30,069 |  | 30,466
Financing Receivable, Collectively Evaluated for Impairment | 1,550,243 |  | 1,550,243 |  | 1,558,399
Loans and Leases Receivable, Net Amount | $ 1,552,928 |  | $ 1,552,928 |  | $ 1,561,173

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- Definition The recorded investment of impaired financing receivables less than $500,000 that are collectively evaluated. + References No definition available. + Details
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- Definition The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The balance of financing receivables that were collectively evaluated for impairment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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- Definition Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524 + Details
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- Definition Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 + Details
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