Loans and Leases - Leveraged Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Leveraged leases
Leveraged lease equity investment percentage of purchase price	20.00%
Components of net investment in leveraged leases
Rentals receivable, net of principal and interest on non-recourse debt	$ 91,366	$ 107,059
Unearned and deferred income	(21,416)	(23,609)
Investment in leveraged leases	69,950	83,450
Deferred taxes arising from leveraged leases	(21,413)	(28,087)
Net investment in leveraged leases	48,537	55,363
Income from leveraged leases
Pretax income from leveraged leases	2,200	3,000	$ 7,200
Related income tax expense on income from leveraged leases	$ 900	$ 1,200	$ 2,400
Minimum
Leveraged leases
Estimated economic lives	25 years
Maximum
Leveraged leases
Estimated economic lives	34 years
Terms of leveraged lease agreements	26 years