Goodwill and Intangibles (Details Textuals) $ in Thousands	12 Months Ended
Jun. 30, 2018	Dec. 31, 2018 USD ($)
Goodwill [Line Items]
Number of Reporting Units	6
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount	30.00%
Goodwill and Intangibles (Textuals) [Abstract]
Amortization expense for the remainder of 2019		$ 22,200
Amortization expense for 2020		42,600
Amortization expense for 2021		40,200
Amortization expense for 2022		37,800
Amortization expense for 2023		35,400
Amortization expense for 2024		31,000
Service Center Based Distribution Segment [Member]
Goodwill [Line Items]
Accumulated goodwill impairment losses		64,794
Fluid Power Businesses Segment [Member]
Goodwill [Line Items]
Accumulated goodwill impairment losses		$ 36,605

Goodwill and intangibles.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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Percentage of fair value of reporting unit in excess of carrying amount.

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