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Allowance for Loan Losses - Recorded Investment in Commercial Loan Classes by Internally Assigned Risk Ratings (Details) - Commercial - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 4,660,290 | $ 4,672,445
Total percentage of recorded investment in commercial loan | 100.00% | 100.00%
Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 4,406,993 | $ 4,403,909
Total percentage of recorded investment in commercial loan | 94.60% | 94.30%
Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 88,037 | $ 87,344
Total percentage of recorded investment in commercial loan | 1.90% | 1.80%
Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 165,260 | $ 181,192
Total percentage of recorded investment in commercial loan | 3.50% | 3.90%
Commercial real estate |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 2,901,625 | $ 2,921,832
Total percentage of recorded investment in commercial loan | 100.00% | 100.00%
Commercial real estate | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 2,745,156 | $ 2,776,292
Total percentage of recorded investment in commercial loan | 94.60% | 95.00%
Commercial real estate | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 56,829 | $ 54,627
Total percentage of recorded investment in commercial loan | 2.00% | 1.90%
Commercial real estate | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 99,640 | $ 90,913
Total percentage of recorded investment in commercial loan | 3.40% | 3.10%
Commercial and industrial |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 1,513,007 | $ 1,493,416
Total percentage of recorded investment in commercial loan | 100.00% | 100.00%
Commercial and industrial | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 1,427,120 | $ 1,394,427
Total percentage of recorded investment in commercial loan | 94.30% | 93.40%
Commercial and industrial | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 23,945 | $ 25,368
Total percentage of recorded investment in commercial loan | 1.60% | 1.70%
Commercial and industrial | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 61,942 | $ 73,621
Total percentage of recorded investment in commercial loan | 4.10% | 4.90%
Commercial construction |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 245,658 | $ 257,197
Total percentage of recorded investment in commercial loan | 100.00% | 100.00%
Commercial construction | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 234,717 | $ 233,190
Total percentage of recorded investment in commercial loan | 95.50% | 90.70%
Commercial construction | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 7,263 | $ 7,349
Total percentage of recorded investment in commercial loan | 3.00% | 2.80%
Commercial construction | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 3,678 | $ 16,658
Total percentage of recorded investment in commercial loan | 1.50% | 6.50%

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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=82891408&loc=d3e4428-111522 + Details
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