Purchased Credit Impaired ("PCI") Loans - Summary of PCI Loans by Category (Details) - Covered Loans $ in Thousands	Dec. 31, 2019 USD ($) rating	Dec. 31, 2018 USD ($) rating
Covered Loans [Line Items]
Recorded Investment PCI Loans	$ 90,289	$ 46,401
Commercial and industrial
Covered Loans [Line Items]
Weighted- Average Risk Rating1 | rating	5.65	6.09
Recorded Investment PCI Loans	$ 15,334	$ 2,159
CRE - investor owned
Covered Loans [Line Items]
Weighted- Average Risk Rating1 | rating	7.02	7.19
Recorded Investment PCI Loans	$ 36,903	$ 23,939
CRE - owner occupied
Covered Loans [Line Items]
Weighted- Average Risk Rating1 | rating	6.54	7.39
Recorded Investment PCI Loans	$ 18,915	$ 9,669
Construction and land development
Covered Loans [Line Items]
Weighted- Average Risk Rating1 | rating	5.82	6.03
Recorded Investment PCI Loans	$ 7,893	$ 4,548
Residential real estate
Covered Loans [Line Items]
Weighted- Average Risk Rating1 | rating	6.34	6.40
Recorded Investment PCI Loans	$ 11,069	$ 6,082
Total real estate loans
Covered Loans [Line Items]
Recorded Investment PCI Loans	$ 74,780	$ 44,238
Consumer and other
Covered Loans [Line Items]
Weighted- Average Risk Rating1 | rating	5.10	2.18
Recorded Investment PCI Loans	$ 175	$ 4