Reserves for Expected Costs of Liquidation and Residual Wind-Down Claims (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended			3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended			3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended			3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended	3 Months Ended		6 Months Ended							3 Months Ended	6 Months Ended						3 Months Ended	6 Months Ended						3 Months Ended	6 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Sep. 30, 2011	Jun. 30, 2011	Sep. 30, 2012 Trust Professionals [Member]	Sep. 30, 2011 Trust Professionals [Member]	Sep. 30, 2012 Trust Professionals [Member]	Sep. 30, 2011 Trust Professionals [Member]	Sep. 30, 2012 Trust Governance [Member]	Sep. 30, 2011 Trust Governance [Member]	Sep. 30, 2012 Trust Governance [Member]	Sep. 30, 2011 Trust Governance [Member]	Sep. 30, 2012 Other Administrative Expenses [Member]	Sep. 30, 2011 Other Administrative Expenses [Member]	Sep. 30, 2012 Other Administrative Expenses [Member]	Sep. 30, 2011 Other Administrative Expenses [Member]	Sep. 30, 2012 Reserve for Expected Wind Down Costs [Member]	Sep. 30, 2012 Reserve for Expected Wind Down Costs [Member]	Sep. 30, 2011 Reserve for Expected Wind Down Costs [Member]	Jun. 30, 2011 Reserve for Expected Wind Down Costs [Member]	Sep. 30, 2012 Reserve for Expected Wind Down Costs [Member] Trust Professionals [Member]	Sep. 30, 2011 Reserve for Expected Wind Down Costs [Member] Trust Professionals [Member]	Sep. 30, 2012 Reserve for Expected Wind Down Costs [Member] Trust Professionals [Member]	Sep. 30, 2011 Reserve for Expected Wind Down Costs [Member] Trust Professionals [Member]	Sep. 30, 2012 Reserve for Expected Wind Down Costs [Member] Trust Governance [Member]	Sep. 30, 2011 Reserve for Expected Wind Down Costs [Member] Trust Governance [Member]	Sep. 30, 2012 Reserve for Expected Wind Down Costs [Member] Trust Governance [Member]	Sep. 30, 2011 Reserve for Expected Wind Down Costs [Member] Trust Governance [Member]	Sep. 30, 2012 Reserve for Expected Wind Down Costs [Member] Other Administrative Expenses [Member]	Sep. 30, 2011 Reserve for Expected Wind Down Costs [Member] Other Administrative Expenses [Member]	Sep. 30, 2012 Reserve for Expected Wind Down Costs [Member] Other Administrative Expenses [Member]	Sep. 30, 2011 Reserve for Expected Wind Down Costs [Member] Other Administrative Expenses [Member]	Sep. 30, 2012 Reserve for Expected Reporting Costs [Member]	Sep. 30, 2012 Reserve for Expected Reporting Costs [Member]	Sep. 30, 2011 Reserve for Expected Reporting Costs [Member]	Jun. 30, 2011 Reserve for Expected Reporting Costs [Member]	Sep. 30, 2012 Reserve for Expected Reporting Costs [Member] Trust Professionals [Member]	Sep. 30, 2011 Reserve for Expected Reporting Costs [Member] Trust Professionals [Member]	Sep. 30, 2012 Reserve for Expected Reporting Costs [Member] Trust Professionals [Member]	Sep. 30, 2011 Reserve for Expected Reporting Costs [Member] Trust Professionals [Member]	Sep. 30, 2012 Reserve for Expected Reporting Costs [Member] Trust Governance [Member]	Sep. 30, 2012 Reserve for Expected Reporting Costs [Member] Trust Governance [Member]	Sep. 30, 2012 Reserve for Expected Reporting Costs [Member] Other Administrative Expenses [Member]	Sep. 30, 2011 Reserve for Expected Reporting Costs [Member] Other Administrative Expenses [Member]	Sep. 30, 2012 Reserve for Expected Reporting Costs [Member] Other Administrative Expenses [Member]	Sep. 30, 2011 Reserve for Expected Reporting Costs [Member] Other Administrative Expenses [Member]	Sep. 30, 2012 Reserve for Indenture Trustee/Fiscal and Paying Agent Costs [Member]	Jun. 30, 2012 Reserve for Indenture Trustee/Fiscal and Paying Agent Costs [Member]	Mar. 31, 2012 Reserve for Indenture Trustee/Fiscal and Paying Agent Costs [Member]	Jun. 30, 2011 Reserve for Indenture Trustee/Fiscal and Paying Agent Costs [Member]	Mar. 31, 2011 Reserve for Indenture Trustee/Fiscal and Paying Agent Costs [Member]	Sep. 30, 2012 Reserve for Indenture Trustee/Fiscal and Paying Agent Costs [Member] Trust Governance [Member]	Sep. 30, 2012 Reserve for Indenture Trustee/Fiscal and Paying Agent Costs [Member] Trust Governance [Member]	Sep. 30, 2012 Reserve for Avoidance Action Defense Costs [Member]	Jun. 30, 2012 Reserve for Avoidance Action Defense Costs [Member]	Mar. 31, 2012 Reserve for Avoidance Action Defense Costs [Member]	Jun. 30, 2011 Reserve for Avoidance Action Defense Costs [Member]	Mar. 31, 2011 Reserve for Avoidance Action Defense Costs [Member]	Sep. 30, 2012 Reserve for Avoidance Action Defense Costs [Member] Trust Professionals [Member]	Sep. 30, 2012 Reserve for Avoidance Action Defense Costs [Member] Trust Professionals [Member]	Sep. 30, 2012 Reserve for Residual Wind Down Costs [Member]	Jun. 30, 2012 Reserve for Residual Wind Down Costs [Member]	Mar. 31, 2012 Reserve for Residual Wind Down Costs [Member]	Jun. 30, 2011 Reserve for Residual Wind Down Costs [Member]	Mar. 31, 2011 Reserve for Residual Wind Down Costs [Member]	Sep. 30, 2012 Reserve for Residual Wind Down Costs [Member] Trust Professionals [Member]	Sep. 30, 2012 Reserve for Residual Wind Down Costs [Member] Trust Professionals [Member]	Sep. 30, 2012 Reserve for Residual Wind Down Costs [Member] Other Administrative Expenses [Member]
Summary of activity in reserves for expected costs of liquidation including expected reporting costs
Beginning Balance	$ 66,304	$ 76,111		$ 48,542													$ 45,934	$ 56,815		$ 43,809													$ 15,239	$ 13,320		$ 4,733											$ 572	$ 651	$ 647					$ 1,095	$ 1,240	$ 1,280					$ 2,138	$ 3,240	$ 4,049
Plus:
Funding for expected costs from MLC			52,734																52,734
Additions to (reductions) in reserves	4,678	5,398	5,657														4,265	1,024															413	4,374	5,657
Less liquidation costs incurred (net of reversals):
Liquidation costs incurred					(7,612)	(7,122)	(16,481)	(16,298)	(1,621)	(502)	(3,213)	(1,027)	(86)	(110)	(152)	(258)					(5,848)	(5,045)	(12,339)	(13,375)	(1,077)	(502)	(2,206)	(1,027)	(13)	(50)	(33)	(120)					(517)	(2,077)	(2,056)	(2,923)	(465)	(932)	(73)	(60)	(109)	(138)						(79)	(75)						(145)	(185)						(1,102)	(1,901)	(10)
Ending Balance	$ 61,663	$ 61,663	$ 40,808	$ 48,542													$ 43,261	$ 43,261	$ 38,212	$ 43,809													$ 14,597	$ 14,597	$ 2,596	$ 4,733											$ 572	$ 651	$ 647					$ 1,095	$ 1,240	$ 1,280					$ 2,138	$ 3,240	$ 4,049