Related Party Transactions - Additional information (Detail) (Director, USD $) In Millions, unless otherwise specified	3 Months Ended	4 Months Ended
Sep. 30, 2013	Apr. 30, 2013
Director
Transactions with Third Party [Line Items]
Related party transaction payment for consulting services		$ 0.3
Related party transaction, agreement end date	Apr. 30, 2013

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

Reference 1: 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

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