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
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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, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information
Net sales	$ 564,021	$ 586,221	$ 629,068	$ 592,172	$ 536,616	$ 604,244	$ 684,455	$ 650,492	$ 2,371,482	$ 2,475,807	$ 2,147,770
Operating profit (loss)									200,210	198,788	214,281
Total assets	1,862,595				1,243,893				1,862,595	1,243,893	945,858
Expenditures for long-lived assets									469,188	268,439	153,445
Depreciation and amortization									75,358	67,526	54,727
Purchase of long-lived assets as part of business acquisition									395,600	150,900	65,000
OEM Segment
Segment Reporting Information
Net sales									2,091,901	2,242,616	1,976,623
Aftermarket Segment
Segment Reporting Information
Net sales									279,581	233,191	171,147
Corporate and Other
Segment Reporting Information
Operating profit (loss)									0	0	0
Total assets	99,008				79,863				99,008	79,863	83,623
Depreciation and amortization									$ 0	$ 0	$ 314
Net sales \| OEM Segment
Segment Reporting Information
Consolidated risk, percentage									88.00%	91.00%	92.00%
Net sales \| Aftermarket Segment
Segment Reporting Information
Consolidated risk, percentage									12.00%	9.00%	8.00%
Customer Concentration Risk \| Net sales \| Thor Industries, Inc.
Segment Reporting Information
Consolidated risk, percentage									27.00%	31.00%	38.00%
Customer Concentration Risk \| Net sales \| Berkshire Hathaway Inc.
Segment Reporting Information
Consolidated risk, percentage									21.00%	23.00%	25.00%
Operating Segments
Segment Reporting Information
Net sales									$ 2,371,482	$ 2,475,807	$ 2,147,770
Operating profit (loss)									200,210	198,788	214,281
Total assets	1,763,587				1,164,030				1,763,587	1,164,030	862,235
Expenditures for long-lived assets									469,188	268,439	153,445
Depreciation and amortization									75,358	67,526	54,413
Operating Segments \| OEM Segment
Segment Reporting Information
Net sales									2,091,901	2,242,616	1,976,623
Operating profit (loss)									165,290	167,459	190,276
Total assets	1,167,899				1,034,254				1,167,899	1,034,254	785,926
Expenditures for long-lived assets									166,331	247,895	148,570
Depreciation and amortization									70,136	63,447	50,751
Operating Segments \| Aftermarket Segment
Segment Reporting Information
Net sales									279,581	233,191	171,147
Operating profit (loss)									34,920	31,329	24,005
Total assets	$ 595,688				$ 129,776				595,688	129,776	76,309
Expenditures for long-lived assets									302,857	20,544	4,875
Depreciation and amortization									$ 5,222	$ 4,079	$ 3,662