New Accounting Standards New Accounting Standards (Impact of adoption of ASU 2017-07) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 24, 2017	Sep. 30, 2018	Sep. 24, 2017
New Accounting Pronouncements or Change in Accounting Principle
Motorcycles and Related Products cost of goods sold	$ 776,530	$ 687,823	$ 2,659,740	$ 2,545,884
Selling, administrative and engineering expense	$ 306,665	293,538	$ 909,898	856,606
Adjustments for New Accounting Pronouncement \| Restatement Adjustment
New Accounting Pronouncements or Change in Accounting Principle
Motorcycles and Related Products cost of goods sold		2,700		8,000
Selling, administrative and engineering expense		$ (400)		$ (1,100)

Total costs related to goods produced and sold during the reporting period.

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+ References

No definition available.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=68048583&loc=d3e3636-108311

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