Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands		12 Months Ended
		Jul. 31, 2016		Jul. 31, 2015		Jul. 31, 2014
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits, Income Tax Penalties Expense		$ 0				$ 25
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Tax at statutory rate		35.00%		35.00%		35.00%
Impairment charges (1)	[1]	0.00%		55.80%		(40.30%)
State income taxes, net of federal tax benefit (2)		0.80%	[2]	1.60%	[2]	(1.10%)
International rate differential		0.40%		(2.20%)		(1.30%)
Rate variances arising from foreign subsidiary distributions		0.50%		(0.30%)		(7.50%)
Adjustments to tax accruals and reserves (3)	[3]	(3.70%)		17.80%		25.50%
Research and development tax credits and section 199 manufacturer’s deduction		(3.60%)		(3.90%)		3.60%
Non-deductible divestiture fees and account write-offs		(0.40%)		(4.80%)		(5.20%)
Deferred tax and other adjustments (4)		(1.40%)	[4]	(21.10%)	[4]	0.70%
Other, net		(0.90%)		2.50%		(0.10%)
Effective tax rate		26.70%		80.40%		9.30%
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Goodwill, Impairment Loss				$ 37,112
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Amount				39,800		$ 61,100
Impairment charges		$ 0		$ 46,867		148,551
Effective Income Tax Rate Reconciliation, Tax Credit, Amount						3,100
Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Amount						$ 5,000

[1] (2)The year ended July 31, 2014 includes a $3.1 million increase in valuation allowances against certain state tax credit carryforwards.(3)The years ended July 31, 2014 and 2015 include increases in current year uncertain tax positions, while the year ended July 31, 2016 includes reductions of uncertain tax positions resulting from the closure of audits and lapses in statutes of limitations. (4) The year ended July 31, 2015 includes $5.0 million of foreign tax credit carryforward from the fiscal 2014 U.S. tax return

[2] (2)The year ended July 31, 2014 includes a $3.1 million increase in valuation allowances against certain state tax credit carryforwards.

[3] uncertain tax positions resulting from the closure of audits and lapses in statutes of limitations

[4] The year ended July 31, 2015 includes $5.0 million of foreign tax credit carryforward from the fiscal 2014 U.S. tax return