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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

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

+ References

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- Definition

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

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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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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

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

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Goodwill and Other Intangible Assets - Carrying Amount of Goodwill Attributable to Each Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2016	Mar. 31, 2016	Mar. 31, 2017	Jun. 30, 2016
Goodwill [Line Items]
Goodwill, Foreign Currency Translation Gain (Loss)	$ (4,172)
Goodwill [Roll Forward]
Goodwill			$ 1,078,368	$ 1,082,540
Accumulated impairment losses			(784,053)	(784,053)
Goodwill, Beginning Balance	298,487
Industrial [Member]
Goodwill [Line Items]
Goodwill, Foreign Currency Translation Gain (Loss)	(4,459)
Goodwill [Roll Forward]
Goodwill			404,246	408,705
Accumulated impairment losses			(137,204)	(137,204)
Goodwill, Beginning Balance	271,501
Goodwill, Written off Related to Sale of Business Unit		$ (1,100)
Infrastructure [Member]
Goodwill [Line Items]
Goodwill, Foreign Currency Translation Gain (Loss)	0
Goodwill [Roll Forward]
Goodwill			633,211	633,211
Accumulated impairment losses			(633,211)	(633,211)
Goodwill, Beginning Balance	0
Goodwill, Written off Related to Sale of Business Unit		$ (6,500)
WIDIA [Member]
Goodwill [Line Items]
Goodwill, Foreign Currency Translation Gain (Loss)	287
Goodwill [Roll Forward]
Goodwill			40,911	40,624
Accumulated impairment losses			$ (13,638)	$ (13,638)
Goodwill, Beginning Balance	$ 26,986