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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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Percentage of Purchase Credit Impaired Loans.

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Amount, before valuation allowance, of financing receivable classified as held-for-sale.

+ References

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