Addition to noncurrent assets.

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- Definition

Additions To Noncurrent Assets As Part Of Business Acquisition

+ References

No definition available.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Segment Reporting (Schedule of Information Relating to Segments) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information
Net sales	$ 536,616	$ 604,244	$ 684,455	$ 650,492	$ 547,137	$ 554,814	$ 547,483	$ 498,336	$ 2,475,807	$ 2,147,770	$ 1,678,898
Operating profit (loss)									198,788	214,281	200,850
Total assets	1,243,893				945,858				1,243,893	945,858	786,904
Expenditures for long-lived assets									268,439	153,445	86,602
Depreciation and amortization									67,526	54,727	46,167
Purchase of long-lived assets as part of business acquisition									150,900	65,000	42,000
OEM Segment
Segment Reporting Information
Net sales									2,242,616	1,976,623	1,548,091
Aftermarket Segment
Segment Reporting Information
Net sales									233,191	171,147	130,807
Corporate and Other
Segment Reporting Information
Operating profit (loss)									0	0	0
Total assets	79,863				83,623				79,863	83,623	152,308
Depreciation and amortization									$ 0	$ 314	$ 276
Net sales \| OEM Segment
Segment Reporting Information
Consolidated risk, percentage									91.00%	92.00%	92.00%
Net sales \| Aftermarket Segment
Segment Reporting Information
Consolidated risk, percentage									9.00%	8.00%	8.00%
Customer Concentration Risk \| Net sales \| Thor Industries, Inc.
Segment Reporting Information
Consolidated risk, percentage									31.00%	38.00%	37.00%
Customer Concentration Risk \| Net sales \| Berkshire Hathaway Inc.
Segment Reporting Information
Consolidated risk, percentage									23.00%	25.00%	26.00%
Operating Segments
Segment Reporting Information
Net sales									$ 2,475,807	$ 2,147,770	$ 1,678,898
Operating profit (loss)									198,788	214,281	200,850
Total assets	1,164,030				862,235				1,164,030	862,235	634,596
Expenditures for long-lived assets									268,439	153,445	86,602
Depreciation and amortization									67,526	54,413	45,891
Operating Segments \| OEM Segment
Segment Reporting Information
Net sales									2,242,616	1,976,623	1,548,091
Operating profit (loss)									167,459	190,276	180,850
Total assets	1,034,254				785,926				1,034,254	785,926	569,385
Expenditures for long-lived assets									247,895	148,570	80,588
Depreciation and amortization									63,447	50,751	42,593
Operating Segments \| Aftermarket Segment
Segment Reporting Information
Net sales									233,191	171,147	130,807
Operating profit (loss)									31,329	24,005	20,000
Total assets	$ 129,776				$ 76,309				129,776	76,309	65,211
Expenditures for long-lived assets									20,544	4,875	6,014
Depreciation and amortization									$ 4,079	$ 3,662	$ 3,298