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Loans - Narrative, PCI Loans (Details) - USD ($) | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2020 | Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Loans receivable held-for-sale, amount | $ 0 | $ 0
PCI loans | $ 3,589,359,000 | $ 3,437,085,000
Commercial real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of PCI loans | 22.00% | 29.00%
Commercial and industrial loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of PCI loans | 47.00% | 42.00%
Purchased Credit-Impaired |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
PCI loans | $ 14,775,000 | $ 17,365,000

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