Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Disaggregation of Revenue [Line Items]
Non-interest income from contracts with customers	$ 14,213		$ 27,680
Non-interest income within the scope of other GAAP topics	1,398		2,425
Noninterest Income	15,611	$ 14,921	30,105	$ 33,430
Fees and Commissions, Depositor Accounts [Member]
Disaggregation of Revenue [Line Items]
Non-interest income from contracts with customers	7,323		14,185
Fees and Commissions, Debit Cards [Member]
Disaggregation of Revenue [Line Items]
Non-interest income from contracts with customers	4,532		8,866
Fees and Commissions, Fiduciary and Trust Accounts [Member]
Disaggregation of Revenue [Line Items]
Non-interest income from contracts with customers	1,645		3,214
Other Non-Interest Income [Member]
Disaggregation of Revenue [Line Items]
Non-interest income from contracts with customers	$ 713		$ 1,415