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Allowance for Loan Losses - Recorded Investment in Commercial Loan Classes by Internally Assigned Risk Ratings (Details) - Commercial - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 4,355,395 | $ 3,836,877
Total percentage of recorded investment in commercial loan | 100.00% | 100.00%
Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 4,169,721 | $ 3,653,344
Total percentage of recorded investment in commercial loan | 95.70% | 95.20%
Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 88,198 | $ 83,680
Total percentage of recorded investment in commercial loan | 2.00% | 2.20%
Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 97,476 | $ 99,853
Total percentage of recorded investment in commercial loan | 2.30% | 2.60%
Commercial Real Estate |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 2,498,476 | $ 2,166,603
Total percentage of recorded investment in commercial loan | 100.00% | 100.00%
Commercial Real Estate | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 2,423,742 | $ 2,094,851
Total percentage of recorded investment in commercial loan | 97.00% | 96.70%
Commercial Real Estate | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 33,098 | $ 19,938
Total percentage of recorded investment in commercial loan | 1.30% | 0.90%
Commercial Real Estate | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 41,636 | $ 51,814
Total percentage of recorded investment in commercial loan | 1.70% | 2.40%
Commercial and Industrial |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 1,401,035 | $ 1,256,830
Total percentage of recorded investment in commercial loan | 100.00% | 100.00%
Commercial and Industrial | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 1,315,507 | $ 1,182,685
Total percentage of recorded investment in commercial loan | 93.90% | 94.10%
Commercial and Industrial | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 40,409 | $ 43,896
Total percentage of recorded investment in commercial loan | 2.90% | 3.50%
Commercial and Industrial | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 45,119 | $ 30,249
Total percentage of recorded investment in commercial loan | 3.20% | 2.40%
Commercial Construction |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 455,884 | $ 413,444
Total percentage of recorded investment in commercial loan | 100.00% | 100.00%
Commercial Construction | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 430,472 | $ 375,808
Total percentage of recorded investment in commercial loan | 94.40% | 90.90%
Commercial Construction | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 14,691 | $ 19,846
Total percentage of recorded investment in commercial loan | 3.20% | 4.80%
Commercial Construction | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total recorded investment in commercial loan | $ 10,721 | $ 17,790
Total percentage of recorded investment in commercial loan | 2.40% | 4.30%

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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522 + Details
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