Acquired and Covered Loans - Acquired and Covered Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Acquired Loans [Line Items]
Non-PCI	$ 1,252,361	$ 1,524,453
Total	1,366,229	1,661,906
Acquired loans
Acquired Loans [Line Items]
Non-PCI	1,247,492	1,512,664
Total	1,355,541	1,643,358
Covered loans
Acquired Loans [Line Items]
Non-PCI	4,869	11,789
Total	10,688	18,548
Receivables acquired with deteriorated credit quality
Acquired Loans [Line Items]
PCI	113,868	137,453
Receivables acquired with deteriorated credit quality | Acquired loans
Acquired Loans [Line Items]
PCI	108,049	130,694
Receivables acquired with deteriorated credit quality | Covered loans
Acquired Loans [Line Items]
PCI	$ 5,819	$ 6,759