Other Noninterest Income and Other Noninterest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Operating Cost and Expense [Line Items]
Other Noninterest Income	$ 26,041	$ 35,358	$ 34,170
Other Noninterest Expense	147,063	142,430	145,907
PCI Loans
Other Operating Cost and Expense [Line Items]
Proceeds from Recoveries of Loans Previously Charged off	16,600	21,100	20,100
Telecommunication
Other Operating Cost and Expense [Line Items]
Other Noninterest Expense	10,471	12,172	14,496
Consultant
Other Operating Cost and Expense [Line Items]
Other Noninterest Expense	14,345	14,963	10,931
Core Deposit Intangible Amortization
Other Operating Cost and Expense [Line Items]
Other Noninterest Expense	17,165	17,194	16,851
Advertising
Other Operating Cost and Expense [Line Items]
Other Noninterest Expense	11,650	11,227	10,239
Other Expense
Other Operating Cost and Expense [Line Items]
Other Noninterest Expense	$ 93,432	$ 86,874	$ 93,390