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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

+ Details

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e9038-108599

+ Details

Name:	us-gaap_NoncurrentAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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).

+ 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 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

Name:	us-gaap_Revenues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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.

+ Details

Name:	us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementGeographicalAxis=country_US
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementGeographicalAxis=lnn_InternationalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_PropertyPlantAndEquipmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Industry Segment Information (Schedule Of Revenue By Geographical Areas) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Aug. 31, 2017	May 31, 2017	Feb. 28, 2017	Nov. 30, 2016	Aug. 31, 2016	May 31, 2016	Feb. 29, 2016	Nov. 30, 2015	Aug. 31, 2017	Aug. 31, 2016	Aug. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues	$ 131,937	$ 151,533	$ 124,125	$ 110,390	$ 132,897	$ 141,319	$ 120,573	$ 121,622	$ 517,985	$ 516,411	$ 560,181
Revenues [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues									$ 517,985	$ 516,411	$ 560,181
Percentage									100.00%	100.00%	100.00%
Revenues [Member] \| United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues									$ 297,261	$ 321,554	$ 350,290
Percentage									57.00%	62.00%	63.00%
Revenues [Member] \| International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues									$ 220,724	$ 194,857	$ 209,891
Percentage									43.00%	38.00%	37.00%
Long-Lived Tangible Assets [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Long-Lived Assets	74,498				77,627				$ 74,498	$ 77,627	$ 78,656
Percentage									100.00%	100.00%	100.00%
Long-Lived Tangible Assets [Member] \| United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Long-Lived Assets	54,199				58,098				$ 54,199	$ 58,098	$ 61,332
Percentage									73.00%	75.00%	78.00%
Long-Lived Tangible Assets [Member] \| International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Long-Lived Assets	$ 20,299				$ 19,529				$ 20,299	$ 19,529	$ 17,324
Percentage									27.00%	25.00%	22.00%