Additional Balance Sheet and Cash Flow Information (Inventories, Net) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Inventory [Line Items]
Raw materials and work in process	$ 177,110	$ 161,664
Inventory at lower of FIFO cost or net realizable value	614,767	590,557
Excess of FIFO over LIFO cost	(58,639)	(52,355)
Total inventories, net	556,128	538,202
Obsolescence reserves deducted from FIFO cost	39,000	38,700
Motorcycles
Inventory [Line Items]
Inventory, finished goods, net of inventory valuation adjustment	301,630	289,530
Parts And Accessories And General Merchandise
Inventory [Line Items]
Inventory, finished goods, net of inventory valuation adjustment	$ 136,027	$ 139,363