Financing Arrangements Maturities of Debt (Details) - USD ($) $ in Thousands	Oct. 31, 2018	Jul. 31, 2018	Oct. 31, 2017
Debt Instrument [Line Items]
Long-term Debt	$ 244,038
2019	1,327
2020	2,051
2021	0
2022	243,300
2023	0
Total debt	246,678	$ 246,678	$ 183,092
Insurance Financing Agreement [Member]
Debt Instrument [Line Items]
2019	738
2020	0
2021	0
2022	0
2023	0
Other Debt	738	738	650
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
2019	0
2020	0
2021	0
2022	243,300
2023	0
Long-term Debt	243,300	243,300	178,200
Equipment Security Note [Member]
Debt Instrument [Line Items]
Long-term Debt		0	482
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Capital Leases, Future Minimum Payments Due in Five Years	0
Long-term Debt	2,640	$ 2,640	$ 3,760
2019	589
2020	2,051
2021	0
2022	0
Total	$ 2,640

Amount of minimum lease payments for capital leases.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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