Label	Element	Value
No Load Class \| Texas Pacific Land Corp. [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	47.30%
No Load Class \| Grayscale Bitcoin Trust ETF [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	9.00%
No Load Class \| Hawaiian Electric Industries, Inc. [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	7.20%
No Load Class \| WaterBridge Infrastructure LLC [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	4.70%
No Load Class \| Landbridge Co. LLC [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	4.30%
No Load Class \| Miami International Holdings, Inc. [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	2.80%
No Load Class \| Bolt Data & Energy Inc. [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	2.00%
No Load Class \| Partners Value Investments LP [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	2.00%
No Load Class \| White Mountains Insurance Group Ltd. [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	1.30%
No Load Class \| Permian Basin Royalty Trust [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	1.10%
No Load Class \| Oil and Gas Extraction [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	48.80%
No Load Class \| Cash & Other [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	12.80%
No Load Class \| Securities, Commodity Contracts, and Other Financial Investments and Related Activities [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	9.10%
No Load Class \| Electric Power Generation, Transmission and Distribution [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	7.20%
No Load Class \| Water, Sewage and Other Systems [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	4.70%
No Load Class \| Offices of Real Estate Agents and Brokers [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	4.30%
No Load Class \| Other Investment Pools and Funds [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	2.80%
No Load Class \| Management of Companies and Enterprises [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	2.70%
No Load Class \| Securities and Commodities Exchanges [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	2.70%
No Load Class \| Other Financial Investment Activities [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	2.60%
No Load Class \| Computer Systems Design and Related Services [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	2.30%

No Load Class | Texas Pacific Land Corp. [Member]