Amount of transactions with related party during the financial reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

Name:	us-gaap_RelatedPartyTransactionAmountsOfTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Transactions With Related Parties - Management Agreement (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	May 31, 2016	Jan. 31, 2016	Jan. 31, 2017	Jan. 31, 2016
Transactions with related parties
Management fee		$ 562	$ 188	$ 1,687
AEA Investors LP \| Management agreement
Transactions with related parties
Annual fee	$ 2,250
AEA Investors LP \| Management agreement \| Selling, general and administrative expenses
Transactions with related parties
Management fee			$ 188	$ 1,687