Investments - Additional Information (Details) (USD $)					3 Months Ended						12 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Mar. 31, 2014 Private and venture capital securities [Member]	Jun. 30, 2014 Offshore fund [Member]		Jun. 30, 2013 Offshore fund [Member]		Jun. 30, 2013 Offshore fund [Member] Significant Other Inputs (Level 2) [Member] Energy and natural resource sectors [Member]	Jun. 30, 2014 Corporate debt securities [Member]		Jun. 30, 2014 Trading Securities [Member] Offshore fund [Member]	Jun. 30, 2014 Trading Securities [Member] Offshore fund [Member] Significant Other Inputs (Level 2) [Member] Energy and natural resource sectors [Member]	Jun. 30, 2013 Trading Securities [Member] Offshore fund [Member] Significant Other Inputs (Level 2) [Member] Energy and natural resource sectors [Member]	Jun. 30, 2013 Available-for-sale Securities [Member] Offshore fund [Member] Significant Other Inputs (Level 2) [Member] Dividend paying equity and debt securities [Member]	Jun. 30, 2013 Available-for-sale Securities [Member] Corporate debt securities [Member] Significant Other Inputs (Level 2) [Member]	Dec. 31, 2013 Government Fund [Member] Mutual Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Fair value of investments held	$ 24,013,000		$ 13,811,000
Cost basis of investments held	22,900,000
Market value of investments to Company's total assets	63.40%
Other investments	1,413,000		0
Percentage of financial assets derived from Level 1 inputs measured at fair value	90.00%		58.00%
Percentage of financial assets derived from Level 2 inputs measured at fair value	9.00%		40.00%
Percentage of financial assets derived from Level 3 inputs measured at fair value	1.00%		2.00%
Trading, fair value	17,817,000	[1]	4,758,000	[1]		998,000	[1]	786,000	[1]	786,000				998,000	786,000			14,100,000
Minimum redemption notice													45 days
Available-for-sale securities, fair value	6,196,000	[2],[3]	9,053,000	[2],[3]				4,712,000	[3]		1,632,000	[3]				4,700,000	1,100,000
Other Investments transferred out of Level 3 assets					$ 385,000						$ 0

[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 June 30, 2014, are $1,345 and $888, 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 (loss) as a separate component of shareholders’ equity until realized.