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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 |
--- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Unpaid principal balance | $ 1,108,379 | $ 1,155,034 |
Allowance for loan and lease losses | 223,116 |  | $ 221,893
Loans and Leases Receivable, Net Amount | 23,388,861 |  | 23,374,932
Non-PCI impaired loans less than $500,000 collectively evaluated | 46,900 |  | 49,100
PCI Loans |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Acquired loans which have adverse change in expected cash flows | 170,400 |  | 279,800
Provision for Loan, Lease, and Other Losses | 2,354 | (2,845) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 84 | 0 |
Recoveries | 0 | 0 |
PCI Loans | Commercial | Construction and land development |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Provision for Loan, Lease, and Other Losses | 310 | (186) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 0 | 0 |
Recoveries | 0 | 0 |
PCI Loans | Commercial | Mortgage |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Provision for Loan, Lease, and Other Losses | 1,608 | (1,230) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 84 | 0 |
Recoveries | 0 | 0 |
PCI Loans | Commercial | Other commercial real estate |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Provision for Loan, Lease, and Other Losses | (46) | (158) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 0 | 0 |
Recoveries | 0 | 0 |
PCI Loans | Commercial | Commercial and industrial |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Provision for Loan, Lease, and Other Losses | 13 | (142) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 0 | 0 |
Recoveries | 0 | 0 |
PCI Loans | Noncommercial | Construction and land development |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Provision for Loan, Lease, and Other Losses | (50) | 0 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 0 | 0 |
Recoveries | 0 | 0 |
PCI Loans | Noncommercial | Consumer and Other |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Provision for Loan, Lease, and Other Losses | 46 | (34) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 0 | 0 |
Recoveries | 0 | 0 |
PCI Loans | Noncommercial | Mortgage |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Provision for Loan, Lease, and Other Losses | 264 | (545) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 0 | 0 |
Recoveries | 0 | 0 |
PCI Loans | Noncommercial | Revolving mortgage |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Provision for Loan, Lease, and Other Losses | 209 | (550) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 0 | 0 |
Recoveries | 0 | 0 |
Non-PCI Loans |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total impaired noncovered loans and leases | 155,950 |  | 155,646
Unpaid principal balance | 172,656 |  | 170,034
Impaired Financing Receivable, Related Allowance | 9,866 |  | 9,728
ALLL for loans and leases individually evaluated for impairment | 9,866 |  | 9,728
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 82,789 |  | 77,199
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 73,161 |  | 78,447
Financing Receivable, Individually Evaluated for Impairment | 155,950 |  | 155,646
Average balance | 155,025 | 136,679 |
Interest income recognized | 1,372 | 1,148 |
Provision for Loan, Lease, and Other Losses | 5,251 | 11,076 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 9,613 | 8,709 |
Recoveries | 3,315 | 2,626 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 200,954 |  | 202,139
Financing Receivable, Collectively Evaluated for Impairment | 22,752,190 |  | 22,678,181
Loans and Leases Receivable, Net Amount | 22,908,140 |  | 22,833,827
Non-PCI Loans | Commercial | Construction and land development |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Unpaid principal balance | 1,461 |  | 1,110
ALLL for loans and leases individually evaluated for impairment | 171 |  | 185
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 740 |  | 788
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 391 |  | 0
Financing Receivable, Individually Evaluated for Impairment | 1,131 |  | 788
Average balance | 1,155 | 1,055 |
Interest income recognized | 11 | 12 |
Provision for Loan, Lease, and Other Losses | 2,225 | 2,536 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 0 | 77 |
Recoveries | 23 | 55 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 26,547 |  | 24,285
Financing Receivable, Collectively Evaluated for Impairment | 737,282 |  | 668,427
Loans and Leases Receivable, Net Amount | 738,413 |  | 669,215
Non-PCI Loans | Commercial | Mortgage |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Unpaid principal balance | 75,584 |  | 78,936
ALLL for loans and leases individually evaluated for impairment | 3,521 |  | 3,648
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 37,100 |  | 39,135
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 33,177 |  | 34,520
Financing Receivable, Individually Evaluated for Impairment | 70,277 |  | 73,655
Average balance | 72,267 | 75,310 |
Interest income recognized | 711 | 642 |
Provision for Loan, Lease, and Other Losses | (1,365) | 6 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 46 | 37 |
Recoveries | 239 | 364 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 40,312 |  | 41,357
Financing Receivable, Collectively Evaluated for Impairment | 9,788,859 |  | 9,655,367
Loans and Leases Receivable, Net Amount | 9,859,136 |  | 9,729,022
Non-PCI Loans | Commercial | Other commercial real estate |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Unpaid principal balance | 1,614 |  | 2,267
ALLL for loans and leases individually evaluated for impairment | 306 |  | 209
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 1,086 |  | 1,351
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 413 |  | 506
Financing Receivable, Individually Evaluated for Impairment | 1,499 |  | 1,857
Average balance | 1,713 | 1,584 |
Interest income recognized | 11 | 8 |
Provision for Loan, Lease, and Other Losses | (1,293) | 304 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 0 | 5 |
Recoveries | 145 | 4 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 3,117 |  | 4,362
Financing Receivable, Collectively Evaluated for Impairment | 385,235 |  | 471,576
Loans and Leases Receivable, Net Amount | 386,734 |  | 473,433
Non-PCI Loans | Commercial | Commercial and industrial |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Unpaid principal balance | 10,882 |  | 10,475
ALLL for loans and leases individually evaluated for impairment | 621 |  | 665
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 5,514 |  | 6,326
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 2,097 |  | 1,648
Financing Receivable, Individually Evaluated for Impairment | 7,611 |  | 7,974
Average balance | 7,524 | 11,529 |
Interest income recognized | 76 | 104 |
Provision for Loan, Lease, and Other Losses | (425) | 3,592 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 1,475 | 3,253 |
Recoveries | 1,219 | 265 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 52,395 |  | 53,032
Financing Receivable, Collectively Evaluated for Impairment | 2,687,594 |  | 2,722,433
Loans and Leases Receivable, Net Amount | 2,695,205 |  | 2,730,407
Non-PCI Loans | Commercial | Lease financing |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Unpaid principal balance | 3,610 |  | 2,571
ALLL for loans and leases individually evaluated for impairment | 494 |  | 397
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 1,896 |  | 1,890
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 270 |  | 24
Financing Receivable, Individually Evaluated for Impairment | 2,166 |  | 1,914
Average balance | 2,238 | 1,568 |
Interest income recognized | 11 | 14 |
Provision for Loan, Lease, and Other Losses | 987 | 575 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 854 | 173 |
Recoveries | 41 | 6 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 5,807 |  | 5,730
Financing Receivable, Collectively Evaluated for Impairment | 908,423 |  | 892,887
Loans and Leases Receivable, Net Amount | 910,589 |  | 894,801
Non-PCI Loans | Commercial | Other |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Unpaid principal balance |  |  | 521
ALLL for loans and leases individually evaluated for impairment | 0 |  | 0
Impaired Financing Receivable, with Related Allowance, Recorded Investment |  |  | 0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment |  |  | 521
Financing Receivable, Individually Evaluated for Impairment | 0 |  | 521
Average balance | 0 | 196 |
Interest income recognized | 0 | 2 |
Provision for Loan, Lease, and Other Losses | 114 | 517 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 3 | 123 |
Recoveries | 42 | 13 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 4,842 |  | 4,689
Financing Receivable, Collectively Evaluated for Impairment | 281,485 |  | 301,655
Loans and Leases Receivable, Net Amount | 281,485 |  | 302,176
Non-PCI Loans | Noncommercial | Construction and land development |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Unpaid principal balance | 4,620 |  | 5,224
ALLL for loans and leases individually evaluated for impairment | 82 |  | 68
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 1,294 |  | 592
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 2,509 |  | 3,959
Financing Receivable, Individually Evaluated for Impairment | 3,803 |  | 4,551
Average balance | 4,104 | 2,605 |
Interest income recognized | 48 | 33 |
Provision for Loan, Lease, and Other Losses | 107 | (83) |
Financing Receivable, Allowance for Credit Losses, Write-downs | 182 | 0 |
Recoveries | 26 | 0 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 3,831 |  | 3,894
Financing Receivable, Collectively Evaluated for Impairment | 239,311 |  | 243,738
Loans and Leases Receivable, Net Amount | 243,114 |  | 248,289
Non-PCI Loans | Noncommercial | Mortgage |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Unpaid principal balance | 44,065 |  | 39,946
ALLL for loans and leases individually evaluated for impairment | 2,905 |  | 2,733
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 23,417 |  | 19,135
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 17,930 |  | 18,707
Financing Receivable, Individually Evaluated for Impairment | 41,347 |  | 37,842
Average balance | 38,724 | 32,963 |
Interest income recognized | 275 | 253 |
Provision for Loan, Lease, and Other Losses | 1,512 | 1,351 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 806 | 250 |
Recoveries | 77 | 287 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 13,584 |  | 12,973
Financing Receivable, Collectively Evaluated for Impairment | 3,546,444 |  | 3,485,944
Loans and Leases Receivable, Net Amount | 3,587,791 |  | 3,523,786
Non-PCI Loans | Noncommercial | Revolving mortgage |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Unpaid principal balance | 27,948 |  | 25,941
ALLL for loans and leases individually evaluated for impairment | 1,053 |  | 1,085
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 9,998 |  | 5,875
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 15,527 |  | 17,895
Financing Receivable, Individually Evaluated for Impairment | 25,525 |  | 23,770
Average balance | 24,792 | 7,969 |
Interest income recognized | 201 | 57 |
Provision for Loan, Lease, and Other Losses | 466 | 550 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 992 | 825 |
Recoveries | 194 | 552 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 21,051 |  | 21,351
Financing Receivable, Collectively Evaluated for Impairment | 2,626,123 |  | 2,677,755
Loans and Leases Receivable, Net Amount | 2,651,648 |  | 2,701,525
Non-PCI Loans | Noncommercial | Consumer |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Unpaid principal balance | 2,872 |  | 3,043
ALLL for loans and leases individually evaluated for impairment | 713 |  | 738
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 1,744 |  | 2,107
Impaired Financing Receivable, with No Related Allowance, Recorded Investment | 847 |  | 667
Financing Receivable, Individually Evaluated for Impairment | 2,591 |  | 2,774
Average balance | 2,508 | 1,900 |
Interest income recognized | 28 | 23 |
Provision for Loan, Lease, and Other Losses | 2,923 | 1,728 |
Financing Receivable, Allowance for Credit Losses, Write-downs | 5,255 | 3,966 |
Recoveries | 1,309 | $ 1,080 |
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment | 29,468 |  | 30,466
Financing Receivable, Collectively Evaluated for Impairment | 1,551,434 |  | 1,558,399
Loans and Leases Receivable, Net Amount | $ 1,554,025 |  | $ 1,561,173

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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://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -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 The balance of financing receivables that were collectively evaluated for impairment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 balance of financing receivables that were individually evaluated for impairment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -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 allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 + Details
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