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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		11 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Dec. 31, 2017
Income Taxes [Line Items]
Statutory tax rate	21.00%		35.00%
Provision for income taxes	$ 848	$ 206
Unrecognized tax benefits	$ 34,700
U.S. federal tax authorities [Member] | Earliest tax year [Member]
Income Taxes [Line Items]
Income tax examination, year	2013
U.S. federal tax authorities [Member] | Latest tax year [Member]
Income Taxes [Line Items]
Income tax examination, year	2017
U.S. state tax authorities [Member] | Earliest tax year [Member]
Income Taxes [Line Items]
Income tax examination, year	2008
U.S. state tax authorities [Member] | Latest tax year [Member]
Income Taxes [Line Items]
Income tax examination, year	2017
Foreign tax authorities [Member] | Earliest tax year [Member]
Income Taxes [Line Items]
Income tax examination, year	2012
Foreign tax authorities [Member] | Latest tax year [Member]
Income Taxes [Line Items]
Income tax examination, year	2017

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Income taxes.

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of unrecognized tax benefits.

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