Net Assets in Liquidation - Allowed and Disputed General Unsecured Claims and Potential Term Loan Avoidance Action Claims (Parenthetical) (Detail) - USD ($)		3 Months Ended
Dec. 31, 2018	Dec. 31, 2018
Loss Contingency [Abstract]
Amount set aside from distribution for general claim contingency	$ 14,800,000
Distributable cash per $1000 of allowed general claim		$ 296

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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