Borrowed Funds - Summary of Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Debt issue costs and unamortized premium	$ (2,013)	$ (2,350)
Total senior and subordinated debt	232,987	232,650
Cadence Bancorporation
Debt Instrument [Line Items]
Long-term debt, gross	210,000	210,000
Cadence Bancorporation \| 5.375% Senior Notes, Due June 28, 2021
Debt Instrument [Line Items]
Long-term debt, gross	50,000	50,000
Cadence Bancorporation \| 7.250% Subordinated Notes, Due June 28, 2029, Callable in 2024
Debt Instrument [Line Items]
Long-term debt, gross	35,000	35,000
Cadence Bancorporation \| 6.500% Subordinated Notes, Due March 2025, Callable in 2020
Debt Instrument [Line Items]
Long-term debt, gross	40,000	40,000
Cadence Bancorporation \| 4.750% Subordinated Notes, Due June 2029, Callable in 2024
Debt Instrument [Line Items]
Long-term debt, gross	85,000	85,000
Cadence Bank \| 6.250% Subordinated Notes, Due June 28, 2029, Callable in 2024
Debt Instrument [Line Items]
Long-term debt, gross	$ 25,000	$ 25,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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