Loans and Leases (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Receivables [Abstract]
Loans and leases, deferred fees and costs	$ 73,600	$ 73,600	$ 70,400
Discounts on acquired loans	37,000	37,000	50,000
Total loans pledged to secure borrowings	13,400,000	13,400,000
Outstanding contractual unpaid principal balance of non-covered purchased impaired loans	146,300	146,300	183,700
Financing Receivable, Allowance for Credit Loss [Line Items]
Interest income recognized on leases	8,100	24,600
Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans acquired with deteriorated credit quality	$ 104,836	$ 104,836	$ 134,500	$ 144,984
Minimum
Financing Receivable, Allowance for Credit Loss [Line Items]
Lease term	3 years	3 years
Maximum
Financing Receivable, Allowance for Credit Loss [Line Items]
Lease term	5 years	5 years