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
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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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.

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Segment Reporting (Details Textual) $ in Thousands			12 Months Ended
Segment Reporting (Details Textual) $ in Thousands	Oct. 01, 2017 segment	Apr. 01, 2017 segment	Dec. 31, 2017 USD ($) segment	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of segments \| segment	1	2	3
Depreciation expense			$ 1,255,175	$ 1,187,050	$ 1,121,966
Acquisition payments			7,240	0	0
Central support service assets depreciation expense allocated to other business segments
Segment Reporting Information [Line Items]
Depreciation expense			$ 24,000	$ 24,000	$ 22,000
Automotive industry \| Supply Chain Solutions
Segment Reporting Information [Line Items]
Percentage of total revenue			40.00%	44.00%	41.00%