Business realignment charges - Business segment information (Details) $ in Thousands	3 Months Ended
Sep. 30, 2018 USD ($) employee	Sep. 30, 2017 USD ($) employee
Other expense
Restructuring Cost and Reserve [Line Items]
Realignment charges and acquisition integration costs	$ 55	$ 0
Diversified Industrial
Restructuring Cost and Reserve [Line Items]
Realignment charges and acquisition integration costs	$ 8,558	$ 13,263
Number of positions eliminated (by employees) \| employee	201	542
Aerospace Systems
Restructuring Cost and Reserve [Line Items]
Realignment charges and acquisition integration costs	$ 0	$ 763
Number of positions eliminated (by employees) \| employee	0	37

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration