Premises and Equipment, Minimum Annual Rent Under Operating Lease Agreements (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Payments, 2018	$ 9,815
Payments, 2019	9,686
Payments, 2020	8,886
Payments, 2021	8,085
Payments, 2022	5,796
Payments, thereafter	22,447
Payments, total	64,715
Operating Leases, Future Minimum Payments Receivable [Abstract]
Receipts, 2018	3,783
Receipts, 2019	4,415
Receipts, 2020	1,996
Receipts, 2021	1,676
Receipts, 2022	724
Receipts, thereafter	774
Receipts, total	$ 13,368