Investments in Tax-Exempt Bonds Investments of Tax-Exempt Bonds Greens of Pine Glen (Details) (USD $)				12 Months Ended
Feb. 28, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 Greens of Pine Glen [Member]	Feb. 28, 2013 Series A [Member]	Dec. 31, 2012 Series A [Member] Greens of Pine Glen [Member]	Feb. 28, 2013 Series B [Member]	Dec. 31, 2012 Series B [Member] Greens of Pine Glen [Member]
Available-for-Sale Securities, Asset Ownership				100.00%
Available-for-sale Securities, at Par Value		$ 146,806,203	$ 145,907,502	$ 9,500,000		$ 8,515,000		$ 950,000
Debt Instrument, Interest Rate, Stated Percentage	9.00%				6.00%	6.50%	9.00%	12.00%
Available-for-sale Security, Maturity Date at a point in time				Oct. 01, 2047

Interest rate stated in the contractual debt agreement.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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