Income Taxes - 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	$ 2,092,095	$ 2,103,075	$ 2,152,857	$ 2,178,914
Issue costs of limited partnership units capitalized for tax purposes	637,325
Difference in book vs. tax depreciation	45,061
Other	235
Partners' equity for tax purposes	$ 2,774,716