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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 | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018 | Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | $ 161,312 |  | $ 161,312 |  | $ 156,130
Unpaid principal balance | 724,745 | $ 999,926 | 724,745 | $ 999,926 |
Loans and Leases Receivable, Net Amount | 26,969,686 |  | 26,969,686 |  | 25,299,564
Non-PCI impaired loans less than $500,000 collectively evaluated | 42,800 |  | 42,800 |  | 47,100
Commercial |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | 71,972 |  | 71,972 |  | 74,560
Commercial | Construction and land development |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | 1,627 |  | 1,627 |  | 2,298
Commercial | Mortgage |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | 57,270 |  | 57,270 |  | 61,065
Commercial | Other commercial real estate |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | 474 |  | 474 |  | 860
Commercial | Commercial and industrial |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | 12,341 |  | 12,341 |  | 10,046
Commercial | Other |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | 260 |  | 260 |  | 291
Noncommercial |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | 89,340 |  | 89,340 |  | 81,570
Noncommercial | Construction and land development |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | 3,088 |  | 3,088 |  | 2,337
Noncommercial | Consumer and Other |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | 3,208 |  | 3,208 |  | 3,021
Noncommercial | Mortgage |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | 54,237 |  | 54,237 |  | 47,524
Noncommercial | Revolving mortgage |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | 28,807 |  | 28,807 |  | 28,688
PCI Loans |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Recorded Investment | 17,400 |  | 17,400 |  | 18,200
Acquired loans which have adverse change in expected cash flows | 99,000 |  | 99,000 |  | 186,600
Provision for Loan, Lease, and Other Losses | (1,476) | (1,514) | (2,277) | 1,000 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 0 | 0 | 0 | (117) |
Recoveries | 0 | 0 | 0 | 0 |
Non-PCI Loans |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 188,581 |  | 188,581 |  | 163,902
ALLL for loans and leases individually evaluated for impairment | 10,895 |  | 10,895 |  | 9,827
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 118,781 |  | 118,781 |  | 115,073
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 54,343 |  | 54,343 |  | 31,357
Financing Receivable, Individually Evaluated for Impairment | 173,124 |  | 173,124 |  | 146,430
Average balance | 183,713 | 152,381 | 163,161 | 154,152 |
Interest income recognized | 1,373 | 1,350 | 4,013 | 4,092 |
Provision for Loan, Lease, and Other Losses | 8,242 | 2,354 | 25,991 | 15,883 |
Financing Receivable, Allowance for Credit Losses, Write-downs | (9,647) | (9,447) | (30,403) | (28,739) |
Recoveries | 3,123 | 2,939 | 9,802 | 9,277 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 209,063 |  | 209,063 |  | 204,741
Financing Receivable, Collectively Evaluated for Impairment | 26,509,798 |  | 26,509,798 |  | 24,770,270
Loans and Leases Receivable, Net Amount | 26,682,922 |  | 26,682,922 |  | 24,916,700
Non-PCI Loans | Commercial |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 91,319 |  | 91,319 |  | 79,865
ALLL for loans and leases individually evaluated for impairment | 4,423 |  | 4,423 |  | 4,445
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 44,871 |  | 44,871 |  | 43,686
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 38,916 |  | 38,916 |  | 24,955
Financing Receivable, Individually Evaluated for Impairment | 83,787 |  | 83,787 |  | 68,641
Average balance | 91,050 | 76,318 | 78,011 | 80,549 |
Interest income recognized | 705 | 713 | 2,072 | 2,311 |
Non-PCI Loans | Commercial | Construction and land development |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 6,146 |  | 6,146 |  | 2,606
ALLL for loans and leases individually evaluated for impairment | 311 |  | 311 |  | 490
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 2,018 |  | 2,018 |  | 1,897
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 3,695 |  | 3,695 |  | 278
Financing Receivable, Individually Evaluated for Impairment | 5,713 |  | 5,713 |  | 2,175
Average balance | 6,130 | 2,101 | 3,460 | 1,580 |
Interest income recognized | 6 | 27 | 40 | 55 |
Provision for Loan, Lease, and Other Losses | 208 | 8,702 | (3,217) | 7,788 |
Financing Receivable, Allowance for Credit Losses, Write-downs | (116) | (35) | (188) | (43) |
Recoveries | 52 | 136 | 223 | 252 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 31,777 |  | 31,777 |  | 34,780
Financing Receivable, Collectively Evaluated for Impairment | 938,034 |  | 938,034 |  | 755,679
Loans and Leases Receivable, Net Amount | 943,747 |  | 943,747 |  | 757,854
Non-PCI Loans | Commercial | Mortgage |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 69,172 |  | 69,172 |  | 61,317
ALLL for loans and leases individually evaluated for impairment | 2,850 |  | 2,850 |  | 2,671
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 35,222 |  | 35,222 |  | 34,177
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 29,158 |  | 29,158 |  | 21,270
Financing Receivable, Individually Evaluated for Impairment | 64,380 |  | 64,380 |  | 55,447
Average balance | 70,351 | 63,752 | 61,962 | 68,043 |
Interest income recognized | 551 | 583 | 1,653 | 1,953 |
Provision for Loan, Lease, and Other Losses | (1,337) | (2,870) | 4,748 | (3,369) |
Financing Receivable, Allowance for Credit Losses, Write-downs | (1) | (606) | (851) | (1,111) |
Recoveries | 226 | 99 | 502 | 563 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 45,000 |  | 45,000 |  | 40,780
Financing Receivable, Collectively Evaluated for Impairment | 11,388,973 |  | 11,388,973 |  | 10,661,787
Loans and Leases Receivable, Net Amount | 11,453,353 |  | 11,453,353 |  | 10,717,234
Non-PCI Loans | Commercial | Other commercial real estate |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 1,265 |  | 1,265 |  | 946
ALLL for loans and leases individually evaluated for impairment | 12 |  | 12 |  | 42
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 195 |  | 195 |  | 243
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 976 |  | 976 |  | 617
Financing Receivable, Individually Evaluated for Impairment | 1,171 |  | 1,171 |  | 860
Average balance | 1,186 | 950 | 797 | 1,336 |
Interest income recognized | 6 | 10 | 20 | 33 |
Provision for Loan, Lease, and Other Losses | (90) | (1,219) | (230) | (2,044) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 0 | 0 | 0 | (69) |
Recoveries | 0 | 1 | 1 | 147 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 2,240 |  | 2,240 |  | 2,439
Financing Receivable, Collectively Evaluated for Impairment | 489,892 |  | 489,892 |  | 426,125
Loans and Leases Receivable, Net Amount | 491,063 |  | 491,063 |  | 426,985
Non-PCI Loans | Commercial | Commercial and industrial |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 14,456 |  | 14,456 |  | 14,695
ALLL for loans and leases individually evaluated for impairment | 1,191 |  | 1,191 |  | 1,137
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 7,238 |  | 7,238 |  | 7,153
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 5,024 |  | 5,024 |  | 2,715
Financing Receivable, Individually Evaluated for Impairment | 12,262 |  | 12,262 |  | 9,868
Average balance | 13,085 | 9,310 | 11,478 | 9,500 |
Interest income recognized | 140 | 92 | 353 | 269 |
Provision for Loan, Lease, and Other Losses | 4,714 | (5,260) | 10,138 | (907) |
Financing Receivable, Allowance for Credit Losses, Write-downs | (3,047) | (2,106) | (8,327) | (6,874) |
Recoveries | 611 | 497 | 1,748 | 2,399 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 57,988 |  | 57,988 |  | 54,483
Financing Receivable, Collectively Evaluated for Impairment | 4,117,122 |  | 4,117,122 |  | 3,928,862
Loans and Leases Receivable, Net Amount | 4,129,384 |  | 4,129,384 |  | 3,938,730
Non-PCI Loans | Commercial | Other |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 280 |  | 280 |  | 301
ALLL for loans and leases individually evaluated for impairment | 59 |  | 59 |  | 105
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 198 |  | 198 |  | 216
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 63 |  | 63 |  | 75
Financing Receivable, Individually Evaluated for Impairment | 261 |  | 261 |  | 291
Average balance | 298 | 205 | 314 | 90 |
Interest income recognized | 2 | 1 | 6 | 1 |
Provision for Loan, Lease, and Other Losses | 54 | (2,404) | (618) | (2,403) |
Financing Receivable, Allowance for Credit Losses, Write-downs | (42) | (56) | (73) | (98) |
Recoveries | 20 | 117 | 685 | 160 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 2,156 |  | 2,156 |  | 2,116
Financing Receivable, Collectively Evaluated for Impairment | 301,530 |  | 301,530 |  | 296,133
Loans and Leases Receivable, Net Amount | 301,791 |  | 301,791 |  | 296,424
Non-PCI Loans | Noncommercial |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 97,262 |  | 97,262 |  | 84,037
ALLL for loans and leases individually evaluated for impairment | 6,472 |  | 6,472 |  | 5,382
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 73,910 |  | 73,910 |  | 71,387
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 15,427 |  | 15,427 |  | 6,402
Financing Receivable, Individually Evaluated for Impairment | 89,337 |  | 89,337 |  | 77,789
Average balance | 92,663 | 76,063 | 85,150 | 73,603 |
Interest income recognized | 668 | 637 | 1,941 | 1,781 |
Non-PCI Loans | Noncommercial | Construction and land development |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 3,381 |  | 3,381 |  | 4,035
ALLL for loans and leases individually evaluated for impairment | 88 |  | 88 |  | 81
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 1,676 |  | 1,676 |  | 2,337
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 1,412 |  | 1,412 |  | 1,412
Financing Receivable, Individually Evaluated for Impairment | 3,088 |  | 3,088 |  | 3,749
Average balance | 3,124 | 3,190 | 3,473 | 3,607 |
Interest income recognized | 25 | 42 | 93 | 134 |
Provision for Loan, Lease, and Other Losses | 148 | (1,203) | 548 | (1,046) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 0 | 0 | 0 | (219) |
Recoveries | 0 | 0 | 0 | 127 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 2,810 |  | 2,810 |  | 2,269
Financing Receivable, Collectively Evaluated for Impairment | 318,815 |  | 318,815 |  | 253,281
Loans and Leases Receivable, Net Amount | 321,903 |  | 321,903 |  | 257,030
Non-PCI Loans | Noncommercial | Mortgage |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 58,515 |  | 58,515 |  | 45,226
ALLL for loans and leases individually evaluated for impairment | 2,761 |  | 2,761 |  | 1,901
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 44,009 |  | 44,009 |  | 40,359
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 10,302 |  | 10,302 |  | 1,809
Financing Receivable, Individually Evaluated for Impairment | 54,311 |  | 54,311 |  | 42,168
Average balance | 56,029 | 42,601 | 49,048 | 41,124 |
Interest income recognized | 346 | 330 | 988 | 903 |
Provision for Loan, Lease, and Other Losses | 1,024 | (1,828) | 2,903 | 1,176 |
Financing Receivable, Allowance for Credit Losses, Write-downs | (313) | (360) | (957) | (1,455) |
Recoveries | 68 | 128 | 293 | 315 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 14,950 |  | 14,950 |  | 13,571
Financing Receivable, Collectively Evaluated for Impairment | 4,815,251 |  | 4,815,251 |  | 4,223,519
Loans and Leases Receivable, Net Amount | 4,869,562 |  | 4,869,562 |  | 4,265,687
Non-PCI Loans | Noncommercial | Revolving mortgage |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 31,772 |  | 31,772 |  | 31,371
ALLL for loans and leases individually evaluated for impairment | 2,559 |  | 2,559 |  | 2,515
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 25,070 |  | 25,070 |  | 25,751
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 3,660 |  | 3,660 |  | 3,101
Financing Receivable, Individually Evaluated for Impairment | 28,730 |  | 28,730 |  | 28,852
Average balance | 30,067 | 27,503 | 29,477 | 26,228 |
Interest income recognized | 260 | 234 | 763 | 657 |
Provision for Loan, Lease, and Other Losses | (153) | 465 | (272) | 1,220 |
Financing Receivable, Allowance for Credit Losses, Write-downs | (534) | (759) | (1,990) | (2,778) |
Recoveries | 201 | 712 | 1,035 | 1,426 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 18,076 |  | 18,076 |  | 19,347
Financing Receivable, Collectively Evaluated for Impairment | 2,386,154 |  | 2,386,154 |  | 2,514,123
Loans and Leases Receivable, Net Amount | 2,414,884 |  | 2,414,884 |  | 2,542,975
Non-PCI Loans | Noncommercial | Consumer |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |
Unpaid principal balance | 3,594 |  | 3,594 |  | 3,405
ALLL for loans and leases individually evaluated for impairment | 1,064 |  | 1,064 |  | 885
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 3,155 |  | 3,155 |  | 2,940
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 53 |  | 53 |  | 80
Financing Receivable, Individually Evaluated for Impairment | 3,208 |  | 3,208 |  | 3,020
Average balance | 3,443 | 2,769 | 3,152 | 2,644 |
Interest income recognized | 37 | 31 | 97 | 87 |
Provision for Loan, Lease, and Other Losses | 3,674 | 7,971 | 11,991 | 15,468 |
Financing Receivable, Allowance for Credit Losses, Write-downs | (5,594) | (5,525) | (18,017) | (16,092) |
Recoveries | 1,945 | $ 1,249 | 5,315 | $ 3,888 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 34,066 |  | 34,066 |  | 34,956
Financing Receivable, Collectively Evaluated for Impairment | 1,754,027 |  | 1,754,027 |  | 1,710,761
Loans and Leases Receivable, Net Amount | $ 1,757,235 |  | $ 1,757,235 |  | $ 1,713,781

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- Definition Acquired Loans Which Have Adverse Change In Expected Cash Flows + References No definition available. + Details
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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 The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554 + 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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