Fair Value Disclosures - Additional Information (Detail) (USD $)	9 Months Ended
	Mar. 31, 2014		Jun. 30, 2013
Fair Value Assets Liabilities Quantitative Information [Line Items]
Trading, fair value	$ 18,645,573	[1]	$ 4,758,220	[1]
Available-for-sale, fair value	6,240,626	[2],[3]	9,053,111	[2],[3]
Change in unrealized gain (loss)	0
Other investments	385,439		0
Quoted Prices (Level 1)
Fair Value Assets Liabilities Quantitative Information [Line Items]
Percentage of financial assets derived from Level 1 inputs measured at fair value	91.00%		58.00%
Significant Other Inputs (Level 2)
Fair Value Assets Liabilities Quantitative Information [Line Items]
Percentage of financial assets derived from Level 2 inputs measured at fair value	8.00%		40.00%
Significant Unobservable Inputs (Level 3)
Fair Value Assets Liabilities Quantitative Information [Line Items]
Percentage of financial assets derived from Level 3 inputs measured at fair value	1.00%		2.00%
Offshore fund
Fair Value Assets Liabilities Quantitative Information [Line Items]
Trading, fair value	874,000	[1]	786,000	[1]
Available-for-sale, fair value			4,712,000	[3]
Offshore fund | Significant Other Inputs (Level 2)
Fair Value Assets Liabilities Quantitative Information [Line Items]
Available-for-sale, fair value			4,712,205
Offshore fund | Significant Other Inputs (Level 2) | Energy and natural resources sectors
Fair Value Assets Liabilities Quantitative Information [Line Items]
Trading, fair value	874,300		785,990
Corporate debt
Fair Value Assets Liabilities Quantitative Information [Line Items]
Available-for-sale, fair value	1,724,000	[3]
Corporate debt | Significant Other Inputs (Level 2)
Fair Value Assets Liabilities Quantitative Information [Line Items]
Investments, fair value	$ 1,128,640
Trading securities | Offshore fund | Significant Other Inputs (Level 2)
Fair Value Assets Liabilities Quantitative Information [Line Items]
Redemption description of investment	First business day of each month after providing a redemption notice at least forty-five days prior to the proposed redemption date.
Minimum redemption notice period of investment	45 days

[1] Unrealized and realized gains and losses on trading securities are included in earnings in the statement of operations.

[2] Net unrealized gains on available-for-sale securities gross and net of tax as of March 31, 2014, are $1,129 and $745, respectively, and as of June 30, 2013, are $988 and $652, respectively.

[3] Unrealized gains and losses on available-for-sale securities are excluded from earnings and recorded in other comprehensive income as a separate component of shareholders’ equity until realized.