Employee Benefit Plans and Other Postretirement Benefits (Schedule Of Fair Value Of Pension Plan and Postretirement Healthcare Plan Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Plan Assets
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	$ 1,874,618	$ 2,162,885
Total assets in the fair value hierarchy excluding assets measured at net asset value	1,858,192	2,148,684
Pension Plan Assets | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	1,149,386	1,368,474
Pension Plan Assets | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	708,806	780,210
Pension Plan Assets | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	40,984	51,082
Pension Plan Assets | Cash and cash equivalents | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	1,057
Pension Plan Assets | Cash and cash equivalents | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	40,984	50,025
Pension Plan Assets | Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	1,076,467	1,283,092
Pension Plan Assets | Equity Securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	1,061,618	1,265,676
Pension Plan Assets | Equity Securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	14,849	17,416
Pension Plan Assets | U.S. companies
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	636,308	722,527
Pension Plan Assets | U.S. companies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	621,459	705,111
Pension Plan Assets | U.S. companies | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	14,849	17,416
Pension Plan Assets | Foreign companies
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	66,143	78,765
Pension Plan Assets | Foreign companies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	66,143	78,765
Pension Plan Assets | Foreign companies | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Pension Plan Assets | Harley-Davidson common stock
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	43,455	64,800
Pension Plan Assets | Harley-Davidson common stock | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	43,455	64,800
Pension Plan Assets | Harley-Davidson common stock | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Pension Plan Assets | Pooled equity funds
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	330,476	416,881
Pension Plan Assets | Pooled equity funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	330,476	416,881
Pension Plan Assets | Pooled equity funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Pension Plan Assets | Other
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	85	119
Pension Plan Assets | Other | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	85	119
Pension Plan Assets | Other | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Pension Plan Assets | Fixed-income holdings
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	740,741	814,510
Pension Plan Assets | Fixed-income holdings | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	87,768	101,741
Pension Plan Assets | Fixed-income holdings | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	652,973	712,769
Pension Plan Assets | U.S. Treasuries
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	45,102	39,866
Pension Plan Assets | U.S. Treasuries | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	45,102	39,866
Pension Plan Assets | U.S. Treasuries | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Pension Plan Assets | Federal agencies
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	27,811	29,188
Pension Plan Assets | Federal agencies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Pension Plan Assets | Federal agencies | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	27,811	29,188
Pension Plan Assets | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	434,070	462,563
Pension Plan Assets | Corporate bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Pension Plan Assets | Corporate bonds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	434,070	462,563
Pension Plan Assets | Pooled fixed income funds
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	140,630	189,361
Pension Plan Assets | Pooled fixed income funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	42,400	61,875
Pension Plan Assets | Pooled fixed income funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	98,230	127,486
Pension Plan Assets | Foreign bonds
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	83,852	81,732
Pension Plan Assets | Foreign bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	266	0
Pension Plan Assets | Foreign bonds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	83,586	81,732
Pension Plan Assets | Municipal bonds
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	9,276	11,800
Pension Plan Assets | Municipal bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Pension Plan Assets | Municipal bonds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	9,276	11,800
Pension Plan Assets | Limited partnership interests
Defined Benefit Plan Disclosure [Line Items]
Assets measured at net asset value	5,918	9,099
Pension Plan Assets | Real estate investment trusts
Defined Benefit Plan Disclosure [Line Items]
Assets measured at net asset value	10,508	5,102
Postretirement Health Coverage
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	190,357	217,537	$ 170,092
Total assets in the fair value hierarchy excluding assets measured at net asset value	184,860	210,787
Postretirement Health Coverage | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	166,713	179,056
Postretirement Health Coverage | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	18,147	31,731
Postretirement Health Coverage | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	5,276	19,317
Postretirement Health Coverage | Cash and cash equivalents | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Postretirement Health Coverage | Cash and cash equivalents | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	5,276	19,317
Postretirement Health Coverage | Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	124,073	144,795
Postretirement Health Coverage | Equity Securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	124,047	144,792
Postretirement Health Coverage | Equity Securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	26	3
Postretirement Health Coverage | U.S. companies
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	86,975	101,720
Postretirement Health Coverage | U.S. companies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	86,949	101,720
Postretirement Health Coverage | U.S. companies | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	26	0
Postretirement Health Coverage | Foreign companies
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	16,342	19,498
Postretirement Health Coverage | Foreign companies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	16,342	19,495
Postretirement Health Coverage | Foreign companies | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	3
Postretirement Health Coverage | Pooled equity funds
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	20,747	23,563
Postretirement Health Coverage | Pooled equity funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	20,747	23,563
Postretirement Health Coverage | Pooled equity funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Postretirement Health Coverage | Other
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	9	14
Postretirement Health Coverage | Other | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	9	14
Postretirement Health Coverage | Other | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Postretirement Health Coverage | Fixed-income holdings
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	55,511	46,675
Postretirement Health Coverage | Fixed-income holdings | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	42,666	34,264
Postretirement Health Coverage | Fixed-income holdings | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	12,845	12,411
Postretirement Health Coverage | U.S. Treasuries
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	8,707	6,803
Postretirement Health Coverage | U.S. Treasuries | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	8,707	6,803
Postretirement Health Coverage | U.S. Treasuries | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Postretirement Health Coverage | Federal agencies
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	5,445	5,060
Postretirement Health Coverage | Federal agencies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Postretirement Health Coverage | Federal agencies | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	5,445	5,060
Postretirement Health Coverage | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	6,590	6,756
Postretirement Health Coverage | Corporate bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Postretirement Health Coverage | Corporate bonds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	6,590	6,756
Postretirement Health Coverage | Pooled fixed income funds
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	33,959	27,461
Postretirement Health Coverage | Pooled fixed income funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	33,959	27,461
Postretirement Health Coverage | Pooled fixed income funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Postretirement Health Coverage | Foreign bonds
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	538	311
Postretirement Health Coverage | Foreign bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Postretirement Health Coverage | Foreign bonds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	538	311
Postretirement Health Coverage | Municipal bonds
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	272	284
Postretirement Health Coverage | Municipal bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Postretirement Health Coverage | Municipal bonds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	272	284
Postretirement Health Coverage | Real estate investment trusts
Defined Benefit Plan Disclosure [Line Items]
Assets measured at net asset value	$ 5,497	$ 6,750