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Purchase Credit Impaired ("PCI") Loans - Summary of PCI Loans by Category (Details) - Covered Loans $ in Thousands | Dec. 31, 2015 USD ($) rating | Dec. 31, 2014 USD ($) rating
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Covered Loans [Line Items] |  |
Recorded Investment PCI Loans | $ 74,758 | $ 99,103
Construction and land development |  |
Covered Loans [Line Items] |  |
Weighted- Average Risk Rating1 | rating | 6.28 | 6.16
Recorded Investment PCI Loans | $ 6,838 | $ 7,740
CRE - owner occupied |  |
Covered Loans [Line Items] |  |
Weighted- Average Risk Rating1 | rating | 6.98 | 7.07
Recorded Investment PCI Loans | $ 25,272 | $ 39,066
CRE - investor owned |  |
Covered Loans [Line Items] |  |
Weighted- Average Risk Rating1 | rating | 6.30 | 6.35
Recorded Investment PCI Loans | $ 19,414 | $ 22,695
Residential real estate |  |
Covered Loans [Line Items] |  |
Weighted- Average Risk Rating1 | rating | 5.44 | 5.54
Recorded Investment PCI Loans | $ 19,287 | $ 25,121
Total real estate loans |  |
Covered Loans [Line Items] |  |
Recorded Investment PCI Loans | $ 70,811 | $ 94,622
Commercial and industrial |  |
Covered Loans [Line Items] |  |
Weighted- Average Risk Rating1 | rating | 6.70 | 6.57
Recorded Investment PCI Loans | $ 3,863 | $ 4,012
Consumer and other |  |
Covered Loans [Line Items] |  |
Weighted- Average Risk Rating1 | rating | 1.89 | 5.39
Recorded Investment PCI Loans | $ 84 | $ 469

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