Schedule II - Liabilities Subject to Compromise (Detail) (USD $) In Thousands, unless otherwise specified	Apr. 30, 2013
Condensed Financial Statements, Captions [Line Items]
Consolidated liabilities subject to compromise	$ 1,704,641us-gaap_LiabilitiesSubjectToCompromise
Predecessor [Member]
Condensed Financial Statements, Captions [Line Items]
Consolidated liabilities subject to compromise	$ 1,704,641

Total amount of liabilities subject to compromise.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 852

-SubTopic 10

-Section 55

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=34712771&loc=d3e56145-112766

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 852

-SubTopic 10

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6916575&loc=d3e55717-112764

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 852

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6918054&loc=d3e56015-112765

Name:	us-gaap_LiabilitiesSubjectToCompromise
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant