Acquired and Covered Loans - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items]
Non-residential mortgage loans with expired loss share agreements	$ 7,800	$ 10,400
Outstanding balance of PCI loans	243,000	175,200
Renewed non-purchased credit impaired loans	523,500	458,000
FDIC indemnification asset	892	2,100	$ 3,300
Acquired and Covered Receivables
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items]
Accretion on acquired loans	$ 35,600	$ 19,500	$ 33,900