Additional Balance Sheet and Cash Flow Information - Inventories, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Inventory [Line Items]
Raw materials and work in process	$ 211,979	$ 235,433
Inventory at lower of FIFO cost or net realizable value	577,580	659,997
Excess of FIFO over LIFO cost	(54,083)	(56,426)
Total inventories, net	523,497	603,571
Obsolescence reserves deducted from FIFO cost	72,000	49,300
Motorcycles
Inventory [Line Items]
Inventory, finished goods, net of inventory valuation adjustment	281,132	280,306
Parts & accessories and general merchandise
Inventory [Line Items]
Inventory, finished goods, net of inventory valuation adjustment	$ 84,469	$ 144,258