Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Noninterest income	$ 40,554	$ 38,010
Noninterest expense	(103,358)	$ (104,196)
Noninterest income from contracts with customers within the scope of ASC 606
Disaggregation of Revenue [Line Items]
Noninterest income	7,645
Service charges and fees on deposit accounts
Disaggregation of Revenue [Line Items]
Noninterest income	4,463
Wealth management revenue
Disaggregation of Revenue [Line Items]
Noninterest income	784
Other charges and fees for customer services
Disaggregation of Revenue [Line Items]
Noninterest income	2,398
Noninterest income within the scope of other GAAP topics
Disaggregation of Revenue [Line Items]
Noninterest income	32,909
Other
Disaggregation of Revenue [Line Items]
Noninterest expense	$ (722)