Loans and Leases (Narrative) (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans and Leases Receivable Disclosure [Abstract]
Interest on non-accrual loans that would have been recorded as additional interest income	$ 9,700	$ 11,300		$ 8,400
Write-down of TDR's		(21,800)	$ (14,300)	$ (3,200)
Sales-type and Direct Financing Leases, Interest Income		$ 5,500