Public Housing Capital Fund Trusts Information Table on Public Housing Capital Fund Trusts (Details) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Principal Outstanding September 30, 2012		$ 59,308,398
Public housing capital fund trusts [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt, Weighted Average Interest Rate	5.00%
Principal Outstanding September 30, 2012	59,308,398
Standard & Poor's, AA- Rating [Member] \| Public Housing Capital Fund Trust I [Member] \| Public housing capital fund trusts [Member]
Schedule of Available-for-sale Securities [Line Items]
Weighted Average Lives (Years)	10 years 0 months 0 days	10 years 3 months 0 days
Investment Rating	AA-	AA-
Debt, Weighted Average Interest Rate	5.30%	5.33%
Principal Outstanding September 30, 2012	25,980,780	25,980,780
Standard & Poor's, A+ Rating [Member] \| Public Housing Capital Fund Trust II [Member] \| Public housing capital fund trusts [Member]
Schedule of Available-for-sale Securities [Line Items]
Weighted Average Lives (Years)	9 years 5 months 20 days	9 years 8 months 20 days
Investment Rating	A+	A+
Debt, Weighted Average Interest Rate	4.28%	4.28%
Principal Outstanding September 30, 2012	12,429,186	12,429,186
Standard & Poor's, BBB Rating [Member] \| Public Housing Capital Fund Trust III [Member] \| Public housing capital fund trusts [Member]
Schedule of Available-for-sale Securities [Line Items]
Weighted Average Lives (Years)	10 years 6 months 22 days	10 years 9 months 21 days
Investment Rating	BBB	BBB
Debt, Weighted Average Interest Rate	5.42%	5.42%
Principal Outstanding September 30, 2012	$ 20,898,432	$ 20,898,432

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. This does not include premiums.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

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-Topic 350

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Description of the credit rating indicative of likelihood of repayment of the debt instrument given by a credit rating agency (for example, Standard and Poor's, Moody's, Fitch).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

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-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

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