Income Taxes (Unaudited) - Reconciliation of Partnership Equity Per Financial Statements to Partners' Equity for Tax Purposes (Detail) (USD $)	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Reconciliation Of Gaap Net Income Loss To Taxable Income Loss [Line Items]
Partners' equity per financial statements	$ 3,827,600	$ 3,846,237	$ 4,677,279	$ 4,793,103
Issue costs of limited partnership units capitalized for tax purposes	1,741,677
Difference in book vs. tax depreciation	506,118
Other	84
Partners' equity for tax purposes	$ 6,075,479