Additional Balance Sheet and Cash Flow Information - Inventories, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Inventory [Line Items]
Raw materials and work in process	$ 235,433	$ 177,110
Inventory at lower of FIFO cost or net realizable value	659,997	614,767
Excess of FIFO over LIFO cost	(56,426)	(58,639)
Total inventories, net	603,571	556,128
Obsolescence reserves deducted from FIFO cost	49,300	39,000
Motorcycles
Inventory [Line Items]
Inventory, finished goods, net of inventory valuation adjustment	280,306	301,630
Parts & accessories and general merchandise
Inventory [Line Items]
Inventory, finished goods, net of inventory valuation adjustment	$ 144,258	$ 136,027